At baseline, an aggregated measure of overall neurocognitive functioning and eight neurocognitive measures of working memory, timing (speed/variability), motor control, and intelligence were investigated. Outcomes at follow-up were dimensional measures of ADHD symptom severity and the Kiddie-Global Assessment Scale (K-GAS) for overall functioning. At follow up, affected and unaffected siblings trended to, or fully caught up with performance levels of controls on four (44.4%) and five (55.6%) of the nine dependent variables, respectively. In contrast, performance in remaining key neurocognitive measures  remained impaired at follow-up. Change in neurocognitive functioning was not related to ADHD outcomes. Our results question the etiological link between neurocognitive deficits and ADHD outcomes in adolescents and young adults.Longitudinal studies on the course of neurocognitive functioning of children with ADHD and their unaffected siblings are scarce. Also, it is unclear to what extent that course is related to ADHD outcomes. A carefully phenotyped large sample of 838 Caucasian participants (ADHD-combined type: The online version of this article (10.1007/s10802-018-0449-z) contains supplementary material, which is available to authorized users. Attention-Deficit/Hyperactivity Disorder (ADHD) is characterized by impairing symptoms of inattention and/or hyperactivity/impulsivity , while children with symptoms without neurocognitive dysfunctions may be ‘missed’. This may lead to a distorted view on the role of neurocognitive dysfunctioning in ADHD. A case of Berkson’s bias should thus be considered when there is a longitudinal relationship between neurocognitive functioning and overall functioning. In summary, there is an ongoing debate on the role of  neurocognitive functioning in the emergence and further course of ADHD.From the following models, hypotheses regarding the relationship between neurocognitive functioning (over time) and (ADHD) behavior are derived. Importantly, these models are not necessarily discrete; overlap might exist. One important model is the endophenotype model. This model describes the relationship between neurocognitive functioning and phenotypic characteristics, by stating that neurocognitive functions mediate between the genetic liability for the disorder and the phenotypic expression , these unaffected siblings may be at-risk for developing a full diagnosis. However, in unaffected siblings, developmental outcomes can be studied independent of an ADHD diagnosis and treatment for ADHD at study entry. To our knowledge, unaffected siblings have not yet been studied longitudinally in relation to neurocognitive functioning. Cross-sectional studies of neurocognitive functioning in unaffected siblings showed mixed results: Unaffected siblings showing worse performance than controls . We investigated the neurocognitive course of these three groups of children to achieve two aims. First, we investigated the neurocognitive course in multiple domains  comparing ADHD affected and unaffected siblings with controls. Participants were between 5 and 19 years old at baseline and re-assessed on average six years later when they were between 11 and 25 years old. Second, we mapped the course of neurocognitive functioning in multiple domains onto dimensional ADHD outcomes  at follow-up, over and above baseline ADHD severity, carefully taking into account the effects of age. As several theoretical models exist on the course of neurocognitive functioning and its relationship with ADHD outcomes, and these models formulate contrasting ideas, we did not formulate hypotheses. Rather, we discussed which model(s) best fitted our results.The current study improves upon shortcomings of earlier studies, by prospectively studying a large sample of extensively phenotyped ADHD affected and unaffected siblings, and controls (N = 1092) was contacted and invited for follow-up on average 5.9 years (SD = 0.8) after enrolment; 76.7% (N = 838) was retained successfully. Attrition analyses are described in Supplement A sample of 838 participants with ADHD combined type , their unaffected siblings, and controls, aged 5 to 19 years at baseline, participated in this study. The sample was part of a follow-up study of the Dutch branch of the International Multicenter ADHD Genetics (IMAGE) study ; 271 unaffected siblings , and 228 controls .Selection and diagnostic procedures at baseline . Included were verbal working memory . Baseline ADHD symptom severity was measured by scale N of the CPRS-R:L, and impairment at baseline was measured by the impairment scale of the Strengths and Difficulties Questionnaires  affected siblings (AS) versus controls, and (1b) unaffected siblings (US) versus controls. For all neurocognitive measures, we tested a group-by-time (baseline to follow-up) interaction-effect using a full-factorial model. In all models, family and subject were tested as random effects to account for within family correlation and for correlated measurements over time. Group was used as a fixed factor, and time as a repeated measure. Significance thresholds were set at 0.05. Please see for specific details regarding data preparation Supplement a affecteIn all analyses age at baseline and follow-up interval were included as covariates by default. Further, it was checked whether sex, pharmacological treatment, study site and the group-by-follow-up interval interaction effect confounded our findings, by adding these variables to the significant models.To explore potentially moderating effects of age, for all significant group-by-time interaction effects we tested the group-by-time (baseline to follow-up)-by-age (at baseline) interactions with a similar analytic procedure as described above. When significant, we retested the group-by-time effect in three equal sized age groups, to explore at which age catch-up has taken place.To investigate whether the course of neurocognitive functioning was related to ADHD outcomes  in affected and unaffected siblings, linear mixed models were used to account for familial dependence, with family as random effect. Change in neurocognitive performance between follow-up and baseline was calculated for each neurocognitive measure separately and used as fixed predictor in the analyses, while follow-up measures of ADHD symptom severity and overall functioning were used as outcome measures. For the time production measure, the statistical analysis differed slightly compared to that of the other variables, see Supplement As there is a strong relationship between baseline and follow-up measures of symptom severity and impairment respectively, the baseline measures were fixed covariates in the respective mixed model-analyses. Age at baseline and follow-up interval were included as covariates by default. Further, when there were significant moderating effects between change in neurocognitive performance and age  on ADHD outcomes, we added the significant interaction effect to the main analysis investigating the relationship between neurocognitive change and outcome measures to account for differential age or group effects. Further, for our main analyses it was checked whether sex, pharmacological treatment, and study site confounded our results, by adding these variables to the significant models.As the results may have been impacted by including children with an IQ < 80, we checked whether results of our main analyses were robust when tested in a sample of children with an IQ ≥ 80.Data quality check revealed that for included participants, 0.0%–1.4% of data per measure needed to be excluded mainly as a result of extreme outliers. As linear mixed models were used, these missing data points were taken into account by way of maximum likelihood estimation.b = −0.18, p = 0.005; and US vs controls: b = −0.15, p = 0.024). Analysis on single measures of neurocognitive functioning also showed this pattern of catch-up indicated by a significant group x time interaction for time production , time reproduction , time production variability , and motor control . For time production, unaffected siblings showed a stable pattern of slight underestimation of the 1000 ms interval over time, while controls showed overestimation of the 1000 ms interval at baseline and reached the level of (underestimation of) unaffected siblings at follow-up. For the remaining neurocognitive functions , the group x time interaction was not significant. Post hoc analysis showed that for overall neurocognitive functioning, time production and motor control, there was no significant main effect of diagnostic group at follow-up , indicating that full catch-up had taken place. For the other measures, a main effect of diagnostic group was found , indicating that although affected and/or unaffected siblings showed a pattern of catch-up and trended to performance levels of controls, for these measures, performance levels remained behind the level of controls at follow-up.Table p = 0.003), however, when including sex in the model, the group x time interaction effect remained significant (p = 0.001). Group interacted significantly with follow-up interval in the two-way interaction model of time production comparing unaffected siblings with controls (p = 0.028), however, when including the group x follow-up interval interaction effect in the model, the group x time interaction remained significant (p = 0.048). None of the other potentially confounding relationships were significant .Analysis of the possible confounders revealed that sex significantly impacted on the two-way interaction model of time reproduction comparing unaffected siblings with controls , and time reproduction . See Figs. p < 0.007).To explore possible moderating effects of age on the course of neurocognitive functioning for the three diagnostic groups, group x time x age interactions were tested. The group x time x age interaction was significant for time production variability . No further significant relationships between neurocognitive change and either symptom severity or overall functioning at follow-up were observed .Table p = 0.04) and therefore was taken into account as a covariate in all analyses on time reproduction and overall functioning. Both group  and age  did not significantly interact with neurocognitive change, indicating that relationships between neurocognitive change and outcomes were neither dependent on group  nor on age. Analysis of the other possible confounders revealed that pharmacological treatment significantly impacted on the model of time production (p = 0.023), leaving the significant relationship between time production and overall functioning intact (p = 0.003). None of the other potentially confounding relationships were significant .Group interacted significantly with the predictive effects of change in time reproduction on overall functioning (n = 19) were excluded from the analyses. Similar or comparable (non-)significance levels and effect sizes were obtained.Findings on the main analyses regarding the course of neurocognitive functioning and regarding the prediction of ADHD outcome using neurocognitive change replicated when participants with an IQ < 80 (n = 339) and unaffected siblings (n = 271), and controls (n = 228) in childhood/adolescence. In summary, over time, approximately half of the neurocognitive functions in affected and unaffected siblings trended near the level of controls . However, within this trending pattern, only for time production, motor control, and overall neurocognitive functioning full catch-up took place, while for the other functions, there still was some difference in performance at follow-up between the groups. For verbal working memory, reaction time variability, and intelligence, the initial gap between performance of affected and unaffected siblings with controls remained stable over a 6-year period showing similar improvement over time. Importantly, in general, the course of neurocognitive functioning was not related to ADHD outcomes over and above baseline symptom severity or overall functioning in (un)affected siblings, suggesting that improvement/ deterioration of neurocognitive performance does not translate one-to-one into (ADHD) behavior.Despite the central role of neurocognitive impairment in etiological models of ADHD, little is known about the longitudinal course of these neurocognitive characteristics and their relationship with outcomes of ADHD symptoms and overall functioning. The current study is the first to report on this in ADHD affected  causally related to the disorder. For example, the domain of executive functioning includes more functions beside verbal working memory, e.g. visuo-spatial working memory, inhibitory control, set shifting. Also, other executive functioning paradigms  may have been better able to measure verbal working memory abilities compared to the Digit Span task used in the current study  population, including our exclusive focus on individuals with the combined type of ADHD  remained impaired while symptoms improved, and no clear association between neurocognitive change and ADHD outcomes was found at all. Our findings question the etiological link between neurocognitive deficits and ADHD.ESM 1(DOCX 35 kb)


Local governments play an integral role in providing public services to their residents, yet the population health benefits are frequently overlooked, especially when services are outside the traditional health domain. With data from the U.S. Census of Governments and national birth records (spanning from 1992 to 2014), we examined whether local government expenditures on parks and recreation services (PRS) and housing and community development (HCD) predicted county low birth weight outcomes (population incidence and black-white disparities). Hypotheses were tested using bias-corrected county-by-period fixed effects models in a sample of 956 U.S. counties with a total of 3619 observations (observations were defined as three-year pooled estimates), representing 24 million births. Adjusting for prior county low birth weight incidence, levels of total operational, health, and hospital expenditures, and time-varying county sociodemographics, an increase in per capita county PRS expenditures of $50 was associated with 1.25 fewer low birth weight cases per 1000. Change in county HCD expenditures was not associated with low birth weight incidence, and, contrary to hypotheses, neither expenditure type was linked to county black-white disparities. Further examination of the benefits to birth outcomes from increasing parks and recreation services is warranted. •Rising parks and recreation expenditures are linked to declining low birth weight.•Housing and community expenditures are not associated with low birth weight.•‘Health’ was the only expenditure type linked to black-white perinatal disparities.•Benefits of parks and recreation services may include healthier birth outcomes. The relOne health promotion strategy for local governments is to ensure public green spaces and opportunities for physical activity . For exaExpanding access to public parks and recreational opportunities may influence black-white differences in birth outcomes. Black Americans tend to have low access to safe, high-quality parks relative to whites , even whAnother health-relevant public service is housing and community development (HCD) programs—e.g., renewing urban centers, increasing affordable housing stock, and offering housing vouchers . BecauseMoreover, HCD programs could differentially influence LBW incidence for black and white infants. Black adults are more likely to reside in economically disadvantaged urban centers relative to whites  and to bThe current study examines whether changes in local government expenditures for [1] PRS and [2] HCD influence county LBW outcomes—specifically, the LBW incidence rate and the gap in LBW between non-Hispanic blacks and whites. These analyses add to extant literature by offering the first test of the benefits to birth outcomes of local government expenditures on PRS and HCD. Moreover, the explicit focus on black-white differences in LBW introduces a novel policy-relevant predictor to a longstanding research topic. Identifying health-promoting local government practices could generate innovation around budgeting and policy initiatives aimed at improving birth outcomes and reducing racial disparities.22.1Data were derived from multiple sources. National birth records with county identifiers were obtained from the National Center for Health Statistics, spanning the period of 1992–2014. Government expenditures were available from the U.S. Census Bureau's Census of Governments, administered every five years to all counties, municipalities, townships, and special districts  . Survey The sample was refined to singleton births to non-Hispanic white or non-Hispanic black mothers. Eligibility criteria were based on differences in etiology of LBW for singleton and multiple gestation births, and due to our focus on black-white disparities. Of 60.68 million total births in the U.S. during the five assessment periods, 41.02 were singletons to non-Hispanic black or white mothers. Three-year pooled estimates of county-level LBW outcomes were computed and represent: 1992–1994; 1997–1999; 2002–2004; 2007–2009; and 2012–2014. The following inclusion criteria were then applied to counties: at least ten cases of LBW for each racial group  per period to improve reliability; two consecutive periods with concurrent and lagged data; and available data for county variables. The cutpoint of ten LBW cases is similar to prior research . Inclusi2.22.2.1Birth weight is an appropriate focus for the present research for methodological and clinical reasons. LBW  is common relative to infant mortality and reliably measured, important for estimating small area incidence rates. Also, LBW is a major contributor to neonatal mortality and life course outcomes, such as lower educational attainment and higher cardiovascular disease, especially for births <1500 g . FinallyLBW was coded from individual records as <2500 g . Materna2.2.2https://www2.census.gov/govs/pubs/classification/2006_classification_manual.pdf.Two expenditure categories were of primary interest: (1) PRS ; and (2) HCD  . Three eExpenditures were defined as operational costs, including direct employee compensations and costs for supplies, materials, and contractual services. Operational costs financed through grants or transfers were included while intergovernmental transfers to other local governments were excluded to avoid double counting. Operational costs are stable year-to-year relative to capital outlay, such that variation likely reflects distinct shifts in priorities and service provision . Expendi2.2.3County median household income, percent of total residents who are black , and population change were included as time-varying covariates. Median household income estimates come from Small Area Income and Poverty Estimates, based on administrative tax records, government transfers, and Census Bureau data . Where p2.3First, descriptive statistics, histograms, and Pearson correlation coefficients were examined for raw and county mean-centered variables. Outlier data points were winsorized at 4 SD units to reduce violations of linear model assumptions.For study hypotheses, fixed effects models were employed wherein time-invariant between-county differences and period effects were removed. This approach reduces omitted variable bias as stable between county differences are controlled . To modeYti refers to LBW incidence at period t in county i; ai is the time-invariant county effect; Yt−1)i and parks and recreation (PRS) expenditures and LBW incidence, β5xti is a vector of concurrent and lagged time-varying covariates; β6period is a vector for period dummy variables; and eti is the error for period t in county i. The second series of models  followed a parallel progression with black-white absolute gap in LBW as the outcome.Model progression was similar for both outcomes: LBW incidence and black-white gap in LBW. Concurrent local government expenditures  were entered as predictors of LBW incidence, alongside the lagged dependent variable and period dummies (Model 1). Next, lagged local government expenditures for each of the five categories were added (Model 2). Model 3 was further adjusted for time-varying county sociodemographic covariates, and is shown by the following equation:Alternative model specifications were considered , and models were fit using very LBW outcomes. Further description and presentation of results are included in Supplemental Material.3N = 956) were more populous, and had higher black density, median household income, and LBW incidence . Differences in the magnitude of the racial gap in LBW were not considered due to unreliable estimates among excluded counties. Across the study period, mean local government total operational costs were $3235 per capita in 2012 dollars, and only relatively minor shares of expenditures were for HCD (1.9%) and PRS (1.5%). Average HCD expenditures increased from $43 to $74 per capita between 1992 and 2012, and PRS expenditures increased from $38 to $53. Although descriptive statistics indicated skewed distributions for several of the expenditure variables, within county distributions of variables were approximately normally distributed. Within county fluctuations in total operational costs were weakly-to-moderately correlated with HCD, PRS, health, and hospital expenditures (r coefficients ranged from 0.23 to 0.55), whereas fluctuations between expenditure types were at most weakly correlated (rs < 0.17).County descriptors by period are shown in 3.1p = .012), or 0.18 within county SD units in LBW. Fluctuations in HCD expenditures were not significantly associated with LBW incidence in either model. The estimate was in the expected direction but the confidence intervals included 0. When adjusting for county time-varying median household income, black density, and population change (Model 3), the association between PRS expenditures and LBW incidence was of comparable magnitude to earlier estimates and significant. The estimated effect of a $50 per capita increase (and a within county 1 SD unit increase) on LBW incidence is shown for each of the government expenditure types in Results are shown for regression models in 3.2p < .001), with a $50 increase per capita being associated with the racial gap in LBW closing by 1.46 cases per 1000; this finding is discussed in the Supplemental Material.Model results for the county black-white gap in LBW are shown in Table S1 of Supplemental Material. Neither HCD nor PRS expenditures was associated with the county racial gap in LBW, whether expenditures were measured lagged, concurrently, or as change between periods. Of the other expenditures, lagged health expenditures were associated with a shrinking racial gap in LBW incidence over an approximately five-year period , and is therefore of considerable value at the population level. Our study findings are broadly consistent with research on the salubrious effects of residential greenness and green spaces on maternal health and pregnancy outcomes . The majOne potential explanation for the benefits of PRS spending on LBW is via improvements in maternal health in preconception and prenatal periods . PRS expenditures have been shown to increase exercise and time spent in outdoor recreation , and to We did not find a significant association between HCD expenditures and reduced county LBW incidence rate. Although voluminous research exists documenting the health benefits of stable and safe housing , includiStudy strengths include a large sample of counties with multiple waves of data to model within county effects; the use of a large sample of births; and a novel test of the link between local government expenditures and LBW, with an additional focus on county black-white disparities. Nonetheless, study limitations remain. Although the sample of counties included nearly three-quarters of singletons to non-Hispanic white or black mothers, the findings should not be generalized to all U.S. counties. Sample counties tended to be in urban areas located in the Southeastern U.S., and include substantial black populations. Future research should investigate how the association between PRS expenditures and LBW incidence varies by region and urban-rural status.Available data did not allow for modeling of the spatial distribution of new PRS or HCD expenditures. The extent to which services are inequitably distributed would limit the potential for new services to reduce health disparities. For example, one study found that Los Angeles neighborhoods with predominant ethnic minority populations have fewer parks despite denser populations and that new parks exacerbated existing inequities in park access . SimilarAnother limitation is that our modeling strategy did not allow for investigation of between county differences in hypothesized associations. Local government features and the socioeconomic profile of residents influence government spending patterns and thereby the impact on population health. The focus on within county variance over time was preferred as area characteristics are highly collinear, introducing the potential for multiple confounders and limiting the reliability of estimates . As such5The health implications of local government practices and policies are infrequently the focus of scientific inquiry. The role of local governments as service providers, however, has been expanding and the expectations for improvements to human health should follow, particularly among disadvantaged population groups. The current study finds evidence that increases in local government expenditures on PRS are associated with reductions in LBW incidence, independent of changes in total spending and other health-relevant services. If confirmed by future research, policies that focus on increasing PRS expenditures could be used to improve birth outcomes. Given that reductions in LBW incidence would decrease many associated societal costs and have national externalities , there iNone.


SD) is widely understood within social psychology and popular culture as a form of self‐talk that reflects a cognitive state, such as low self‐esteem or negative self‐regard. However, most research on SD suffers theoretical and methodological problems that fail to account for how its cognitive and linguistic aspects can be reconciled. We know little about SD as it occurs in interactional settings. Utilizing a conversation analytic (CA) perspective that brackets cognitive explanations for linguistic phenomena, this paper draws on more than 100 hours of transcribed recordings of interactions from diverse settings to systematically examine the form and function of a common class of SD: critical comments by a speaker on their current talk or actions . Analyses demonstrate that SDMCs are used in environments of possible or actual interactional trouble, and manage this trouble in different sequential positions. The paper shows that SDs can be treated as a communication practice. Rigorous analysis of SDMCs can enrich understanding of the construction of ‘identities’ in talk. It advances a CA understanding of the ascription of social actions, and the preference for self‐criticism over criticism by others. Findings suggest that widespread advice to self‐deprecate less may be invalid.‘Self‐deprecation’ ( By contrast, the preferred response to a self‐deprecation is disagreement: . She argued that overtly agreeing with a self‐deprecation is a dispreferred action because it is tantamount to disaligning with the speaker and endorsing the prior criticism .A handful of studies influenced by linguistics and conversation analysis (CA) have analysed naturally occurring language use to shed light on some of these issues. Pomerantz  examinedPomerantz's research significantly extends what we know about responses to SDs. However, she analysed them in the context of ‘unspecified, friendly conversation’, which impacts the preference structures she identified  that display interactional competence and involve both identity and moral work by the speaker  were not included as examples of SD, but represent a potential avenue for future work.This paper fills this knowledge gap by using CA to systematically examine the composition, sequential position, and interactional function of a common class of SD, namely self‐deprecatory ‘meta‐comments’  is endogenous to the interaction evidenced within the transcript, and hence open to full analytic scrutiny. This contrasts with other classes of SD  where the object of the SD (evidence for the speaker's maths ability) may be exogenous to the interaction analysed. Hence, analyses can help us to understand precisely which features of an interaction are oriented towards and treated by members as particular kinds of social actions .Data consist of a corpus of more than 100 hours of transcribed recordings of interactions from diverse settings:British and American audio and video recordings of ordinary, peer group, and family interactions, recorded in the 1960s and 1970s and used widely by conversation analysts.The ‘Holt’ corpus of British telephone calls between family members, friends, and acquaintances recorded in the 1980s and used widely by conversation analysts.194 routine psychiatric consultations (made up of 156 audio recordings and 38 video recordings) collected from a UK National Health Service Gender Identity Clinic between 2004 and 2008  are implemented and responded to, and through which mutual understanding is arrived at and displayed  that they engendered). Next, analyses identified examples of the sequential environments or ‘slots’ in which SDMCs occur. Instances were selected for inclusion in the paper that show important patterns and variations within each sequence type.Self‐deprecatory meta‐comments are commonly used by speakers in environments of possible or actual interactional trouble, where there are or may be communication difficulties or breakdowns in mutual alignment. SDMCs work to manage or pre‐empt and deflect this trouble in different sequential positions or ‘slots’ relative to the  problematic action sequence. Analyses are divided into sections that reflect these different slots :precede a potentially problematic action sequence (n=6)SDMCs that action‐in‐progress (n=12)SDMCs that address a potentially problematic close potentially problematic action sequences (n=5)SDMCs that expand potentially problematic action sequences (n=19)SDMCs that post hoc, as a ‘last resort’ move to manage the explicit, repeated criticism of the recipient, and transition out of a problematic action sequence (n = 1). I end by considering the implications of these analyses for a social psychological understanding of negative self‐descriptions, and a CA approach to action formation.The majority of SDMCs in the corpus work in a pre‐emptive fashion to name, manage, or deflect interactional troubles that have not been made explicit by the recipient. In section five, by contrast, I consider a deviant case of an SDMC that is used precedes talk that the speaker casts as potentially troublesome or offensive to the recipient. Examples of such ‘forward‐looking’ preliminaries include: ‘I'm going to sound really silly’ (Psychiatric consultation 128) and ‘I'm gonna come over as ageist, I'm gonna come across as a terrible person actually’ (Interview 21). In the first subset of the data, the SDMC Designed to be heard as a maximally built, negative assessment  works rather like a disclaimer . Thus, while the SDMC claims By using the SDMC, the patient is able to get her view ‘on record’ at the same time as demonstrating to the psychiatrist that she is a reflexive analytic being who is attentive to the possibility that her forthcoming talk may be vulnerable to criticism (and hence she is not unthinkingly celebrating gender stereotypes). Indeed, it is perhaps no coincidence that in this ‘gatekeeping’ setting where the patient is required to live as a woman in order to gain access to treatment  to the patient's positive assessment (line 8) by commenting on its implications for the patient's ‘problem’ : . He does not respond to the SDMC itself, by commenting on whether or not she sounded sexist. Indeed, unlike the SDs that Pomerantz  considerIn sum, the SDMC in action‐in‐progress.In the next two instances, the speaker halts the progressivity of the ongoing sequence to deliver an ‘apology plus SDMC’ that addresses a potentially problematic Lesley has called Robbie to discuss some photographs. However, Robbie uses the opportunity afforded by Lesley's call to report troubles with her role as the teacher of a class that Lesley appears to have also taught. Robbie seeks Lesley's advice regarding how to manage a child called Gabriel (lines 1–3 and 9).Following Lesley's advice, a lull materializes where neither party takes the floor (line 18). Robbie initiates a further troubles report (line 19), prefaced with the discourse particle ‘well’, which functions as an alert that the turn in progress ‘will privilege its speaker's perspectives, interests or project relative to the expectations for action established in the prior turn or sequence’ . This account jokingly presents Lesley as partly responsible for any suffering she may be experiencing by virtue of the unfortunate timing of her call , this parenthetical contains an apology for some offence, ‘earful'v this’ (line 20) constitutes an SDMC because it evaluates Robbie's current actions (in this case what she is saying to Leslie – ‘of this’) in negative terms (‘getting an earful’), with the preceding apology treating ‘giving someone an earful’, as an offence. Unlike the SDMC in current (‘you're getting…’) and not forthcoming (‘this is gonna sound…’) actions. Built as an announcement, the SDMC reflexively marks and manages an ongoing offence on the speaker's part that may index a negative identity: in this case as someone who has misappropriated someone else's call to repeatedly offload their troubles .‘You're getting ‘n By using the ‘apology plus SDMC’ format, Robbie demonstrates to Lesley that she is reflexively attuned to the possibility that her ongoing actions may be causing offence, and seeks to be absolved of guilt for that offence, thus pre‐emptively inoculating herself against criticism for it.i:me,hheh ↑heyou obvi]ously don't know who your girlfriend iit's c‐ like=Clai:res Cora:s ‘n:d uh:m uh[tha[t lo:t.]’ . This SDMC announcement serves to mitigate Skip's faux pas as a routine trouble he has with certain names  rather than a one‐off personal failing or something particularly forgettable about Joyce. Joyce does not let Skip ‘off the hook’ but agrees with and embellishes his SDMC, expanding it on his behalf (line 25) , and then by agreeing with the negative assessment that he is very mixed up (line 19). Joyce joins in with the laughter (line 20), before Skip issues the first of two SDMCs: ‘Oh I c'd ell I'm talking t[o .hhh]↑Uhm].hmh’ (line 27). Notice that this SDMC upgrades the prior self‐deprecation which had suggested that Skip had a past problem with specific names, to one that suggests a current, all‐encompassing problem with person identification  is endogenous to the interaction and transcript under investigation, and hence open to full analytic scrutiny.Results demonstrate that SDMCs may be a generic conversational device that works in similar ways across ordinary and institutional settings Drew, : SDMCs apost hoc, and transition out of the problematic action sequence.Analyses demonstrate that SDMCs do ‘identity work’ by managing, pre‐empting and deflecting this trouble, in different sequential positions or ‘slots’ relative to the  problematic action sequence . The majority of SDMCs analysed here named and managed interactional troubles that were implicit within the interaction: The recipient of the SDMC did not explicitly draw attention to these troubles, or criticize the SDMC speaker. dispreferred action because to do so would be tantamount to criticizing the speaker , and their response helps to advance the interactional project of the SDMC speaker (the continuation or closing of the sequence), they can be considered ‘successful’. As Pomerantz has shown, to endorse or agree with an SD would be considered a pre‐emptive fashion as a ‘first resort’ move to inoculate the speaker against criticism , where there is a preference for noticing by others over announcement by self  which are also bound up in the interactional management of identity  as a route to feeling good about ourselves and maintaining positive relationships. Indeed, findings suggest that psychologists may gain a richer understanding of negative self‐descriptions, and the range of mechanisms that are at play when identities are made relevant in talk, by considering the interactional organization of instances of ‘identity talk’ . As Levinson (I want to end by reflecting on the implications of these analyses for a CA understanding of Levinson : 128 notLevinson . AnalysiFor ethical reasons, data cannot be publicly shared, but detailed transcripts are included in the article so that analyses can be independently validated.


Mesenchymal stem cells are heterogenous populations with hematopoietic supporting and immunomodulating capacities. Enormous studies have focused on their preclinical or clinical therapeutic effects, yet the systematic study of continuous in vitro passages on signatures and functions of UC-MSCs at both the cellular and molecular levels is still lacking.+ HSCs to evaluate their hematopoietic supporting capacity in vitro. Finally, we transplanted the cells into acute graft-versus-host disease (aGVHD) mice to further evaluate their therapeutic effect in vivo.In this study, to systematically evaluate the biological properties of MSCs at various passages, we analyzed biomarker expression, cell proliferation and apoptosis, chromosome karyotype, and tri-lineage differentiation potential. Subsequently, we took advantage of whole-exome sequencing to compare the somatic hypermutation of hUC-MSCs at P3, P6, and P15 including SNV and INDEL mutations. In addition, to explore the safety of the abovementioned hUC-MSCs, we performed metabolic pathway enrichment analysis and in vivo transplantation analysis. Furthermore, we cocultured the abovementioned hUC-MSCs with UCB-CD34The hUC-MSCs at P3, P6, and P15 showed similar morphology, biomarker expression, and cytokine secretion. hUC-MSCs at P15 had advantages on adipogenic differentiation and some cytokine secretion such as IL-6 and VEGF, with disadvantages on cell proliferation, apoptosis, and osteogenic and chondrogenic differentiation potential. Based on the SNP data of 334,378 exons and bioinformatic analyses, we found the somatic point mutations could be divided into 96 subsets and formed 30 kinds of signatures but did not show correlation with risk of tumorigenesis, which was confirmed by the in vivo transplantation experiments. However, hUC-MSCs at P15 showed impaired hematologic supporting effect in vitro and declined therapeutic effect on aGVHD in vivo.In this study, we systematically evaluated the biological and genetic properties of hUC-MSCs at various passages. Our findings have provided new references for safety and effectiveness assessments, which will provide overwhelming evidence for the safety of hUC-MSCs after continuous in vitro passages both at the cellular and molecular levels for the first time. Taken together, our studies could help understand the controversial effects of disease treatment and benefit the clinical research of UC-MSCs. Mesenchymal stem cells are acknowledged as the most important niche cells and have broad prospects for regenerative medicine, which mainly due to their unique attributes such as self-renewal, multi-lineage differentiation potential, and hematopoietic supporting effect and immunomodulating function –4. The cClinicalTrials.gov website of NIH, a total number of 983 clinical studies have been registered for series of disease treatment, such as hematological malignancies, acute-on-chronic liver failure, acute severe respiratory failure, type I and II diabetes, psoriasis, graft-versus-host disease (GVHD), cerebral palsy, ulcerative colitis, and even wound healing [To date, according to the  healing –15. Mean healing –19. Of t healing , 21. Mor healing . Recentl healing . However healing , 9.In this study, to illuminate the influence of serial passages on phenotypic characterization, biological function, and molecular genetics of MSCs, we systematically analyzed hUC-MSCs at passages 3, 6, and 15 . Generally, hUC-MSCs at the abovementioned passages showed similarities in cellular morphology, biomarker expression, chromosome karyotype, and most of the cytokine secretion, together with comparable cumulative mutation spectrum. However, when compared to those in the other groups, hUC-MSCs at the higher passage (P15) exhibited impaired cell proliferation capacity, osteogenic and chondrogenic differentiation potential, and hematopoietic supporting effect, but with enhanced apoptosis and adipogenic differentiation potential in vitro. Furthermore, by conducting a GVHD mouse model, we found hUC-MSCs at P15 showed an attenuated therapeutic effect on acute graft-versus-host disease in vivo.6 cells in 10% DMSO in MSC culture medium) as we previously reported [l-glutamine (Gibco), 4 ng/ml bFGF (PeproTECH), 4 ng/ml EGF (PeproTECH), 1% penicillin and streptomycin (ThermoFisher)). The medium was changed every 3 days. When the abovementioned hUC-MSCs reach 80% confluency, the cells were dissociated with 0.25% Trypsin-EDTA at 37 °C for 5 min and resuspended by hUC-MSC culture medium. Then, the hUC-MSCs were collected by centrifugation at 300×g for 5 min. After discarding the supernatant, the cells were resuspended and seeded in the hUC-MSC medium at 37 °C, 5% CO2. Finally, the hUC-MSCs at P3, P6, and P15 were prepared. Three days later, the hUC-MSCs were used for the corresponding tests and analyses.The three independent hUC-MSC lines at various passages  were preserved by our lab using the cryoprotectant  were dissociated into single cells by 0.25% Trypsin-EDTA (Gibco) and stained with the indicated antibodies against CD3, CD4, CD11b, CD14, CD19, CD25, CD29, CD34, CD44, CD45, CD66b, CD73, CD90, CD105, CD127, HLA-DR, Annexin-V, and 7AAD, in 0.2% BSA for 20 min in the dark. After washing with 1× PBS twice, the cells were analyzed by FACS Canto II (BD Biosciences) as we reported previously , P15 wer. The dathUC-MSCs at various passages  were lysed by TRIzol reagent (ThermoFisher) for total RNA collection according to the manufacturer’s instruction. cDNA was synthesized by using TransScript Fly First-Strand cDNA Synthesis SuperMix , and qRT-PCR was performed with the SYBR Green PCR Master Mix (Qiagen) and ABI PRISM 7900 (Applied Biosystems) as we previously reported . The priWestern blotting analysis was conducted as we described before , 25. Bri4/cm2 in MSC culture medium. When cells reached 80% fusion, the medium was changed into adipogenic , osteogenic , or chondrogenic  differentiation medium. The differentiation medium was changed every 3 days as we described previously [hUC-MSCs at various passages P3, P6, P15) were seeded at a density of 2 × 10, P15 wereviously . Twenty-The contents of the secreted cytokines including IL-6, IL-8, VEGF, G-CSF, HGF, TGF-β1, TNF-α, and PGE-2 in the supernatant were quantified using the enzyme-linked immunosorbent assay (ELISA) kits (R&D Systems) according to the manufactures’ instructions as we previously did . The ELIThe chromosome karyotype analysis was performed to monitor the genomic stability of hUC-MSCs at various passages  using a G-banding technique as we previously reported [hUC-MSCs at various passages P3, P6, P15) were used to prepare the whole-exome sequencing samples. For total RNA preparation, the cultured hUC-MSCs (in MSC culture medium) were washed with 1× PBS twice and then lysed by using TRIzol (ThermoFisher) according to the manufacturer’s instructions as we recently reported [, P15 wer137Cs, 30 Gy) when the cells reached 80% confluency. Then, the irradiated hUC-MSCs were dissociated with 0.25% Trypsin-EDTA at 37 °C for 5 min and resuspended by hUC-MSC culture medium. Then, the prepared 2 × 105 hUC-MSCs  were cocultured with 1 × 106 PBMCs at a ratio of 1:5 in IMDM basal medium (Hyclone) supplemented with 10% FBS and 5 ng/μl PHA addition in 37 °C and 5% CO2 incubator. The 1 × 106 PBMCs without hUC-MSC coculture served as a positive control (with 5 ng/μl PHA addition). Seventy-two hours later, the total PBMCs in the supernatant were collected and counted based on trypan blue staining (Procell). Then, the total PBMCs were resuspended in 1× PBS (with 0.2% BSA) and labeled with the indicated antibodies and analyzed by FACS Canto II (BD Biosciences) and FlowJo 7.0 (Ashland). The Th1 cells were labeled with antibodies against CD4 and IFN-γ, the Th2 cells were labeled with antibodies against CD4 and IL-4, the Th17 cells were labeled with antibodies against CD4 and IL17, and the Treg cells were labeled with antibodies against CD4, CD25, and CD127. The antibodies are listed in Additional file Human peripheral blood mononuclear cells (PBMCs) were isolated from the blood of healthy donors by standard Ficoll density gradient centrifugation as we previously reported . hUC-MSC+ HSC enrichment by using magnetic cell sorting. The enriched CD34+ HSCs were then cocultured with hUC-MSCs at various passages  for 14 days in IMDM basal medium (Hyclone) supplemented with 10% FBS in 37 °C and 5% CO2 incubator. Then, HSCs in the supernatant were collected and seeded in methylcellulose semi-solid medium (StemCell Tech) as we reported [Hematopoietic colony-forming unit (CFU) assay was performed as we previously reported with modifications , 26. Bri60Coγ) total body irradiation (TBI). Then, the recipient BALB/c mice were injected 1 × 107 spleen cells and 1 × 107 bone marrow cells from the donor C57BL/6 mice as previously reported with several modifications [5 cells for each mouse at day 6 of the model). Over the next 4 weeks, the clinical and histologic analyses were conducted and recorded as described below.To induce acute GVHD mouse model, the recipient BALB/c mice received a single dose of 10.0 Gy  model, the liver, lung, and skin samples from euthanized mice of each group were fixed with 10% formaldehyde and embedded in paraffin as we described previously , 26. Thet test to analyze the data of two unpaired groups, while one-way ANOVA with Tukey’s post hoc test was used for the data of multiple unpaired groups. Data were shown as mean ± SEM; P < 0.05 were considered statistically significant .Statistical analysis in this study was performed by Prism 6.0 software  as we previously reported , 26, 29.Recently, we and other investigators found the therapeutic effect of MSCs was closely related to cell viability and homing capacity, which was fundamental for clinical application and regenerative medicine , 22. AmoPOU5F1, SOX2, and NANOG were decreased slightly in hUC-MSCs at P15, which were further confirmed at the protein level  or frameshift , while most of the listed genes with variations even with the same origin such as ZNF318, NCOR2, and DOCK5 , together with 10 vital tumor-inhibiting genes  as well; collectively, we did not find new harmful SNP mutations in the abovementioned 21 genes  including single nucleotide polymorphism (SNP) and INDEL mutations by using the MuSic test. From the personalized display of cancer somatic cell panorama mutations, we could intuitively observe the mutation rate, high-frequency mutant genes, and mutation types Fig. e. For ine.g., RRP6, while e.g., RRP6, while e.g., RRP6, while Finally, to further evaluate the safety of MSCs in vivo, we conducted a subcutaneous tumorigenesis test and found there were no tumor structures formed by hUC-MSCs at various passages Fig. g. SimultImmunomodulating and hematopoietic supporting capacities have been recognized as the two unique characteristics of adult MSCs . Origina+ HSC-derived colonies were observed and calculated. When compared with the P3 or P6 group, the numbers of total colonies, G colonies, GM colonies, and even total cells were simultaneously declined in the P15 group  assay as we previously reported [7 bone marrow cells (BMCs) and 1 × 107 spleen cells (SCs) from the donor C57BL/6 mice were mixed and intravenously injected into the recipient BALB/c mice with 10-Gy total body irradiation (TBI) prior to transplantation via the tail vein. After that, the GVHD mice were randomized into the control group (GVHD) with saline injection and the experimental groups with 2 × 105 hUC-MSC  treatment  from three individuals were listed.Additional file 7. The details accompanied with the main manuscript including Additional Figure Legends and Additional Tables were listed.


Indian Buffet Processes and Latent Dirichlet Allocation was proposed to address the urgent need for objective brain-derived measures that can acknowledge shared brain network dysfunction in both disorders. We identified three main variation factors characterized by distinct coupling patterns of the temporoparietal cortices in the default mode network with the dorsal attention and salience network. The brain-derived factors were demonstrated to effectively capture the underlying neural dysfunction shared in both disorders more accurately, and to enable more reliable diagnoses of neurobiological dysfunction. The brain-derived phenotypes alone allowed for a classification accuracy reflecting an underlying neuropathology of 67.33% (+/−3.07) in new individuals, which significantly outperformed the 46.73% (+/−3.97) accuracy of categorical diagnoses. Our results provide initial evidence that shared neural dysfunction in ADHD and ASD can be derived from conventional brain recordings in a data-led fashion. Our work is encouraging to pursue a translational endeavor to find and further study brain-derived phenotypes, which could potentially be used to improve clinical decision-making and optimize treatment in the future.Categorical diagnoses from the Diagnostic and Statistical Manual of Mental Disorders (DSM) or International Classification of Diseases (ICD) manuals are increasingly found to be incongruent with emerging neuroscientific evidence that points towards shared neurobiological dysfunction underlying attention deficit/hyperactivity disorder and autism spectrum disorder. Using resting-state functional magnetic resonance imaging data, functional connectivity of the default mode network, the dorsal attention and salience network was studied in 1305 typically developing and diagnosed participants. A transdiagnostic hierarchical Bayesian modeling framework combining  Both disorders are associated with high levels of family dysfunction, social interaction problems, academic failure, and unemployment and thus constitute a significant burden for children, their families, and society as a whole4: 30–80% of all ASD children meet the diagnostic criteria for ADHD and, conversely, 20–50% of children diagnosed with ADHD also meet the diagnostic criteria for ASD. Both disorders also show similar associated clinical features, including poor social skills, language delay, oppositional defiant behavior, and difficulty with attention and emotion regulation5. This begs the question whether despite superficial differences in clinical presentation both ADHD and ASD share a fundamental mechanism of dysfunction.ADHD is characterized by developmentally inappropriate levels of inattention, impulsivity, and hyperactivity. In contrast, ASD is defined by core symptoms of persistent and pervasive deficits in social communication and interaction along with repetitive behavioral patterns and restricted interests or activities. However, these seemingly disparate disorders have clinical overlap7. Twin studies suggested that 50–72% of phenotypic features are shared by these disorders, potentially reflecting genetic factors common to both ADHD and ASD9. Additionally, genome-wide association studies as well as linkage and candidate gene studies identified a number of genetic risk variants common to both disorders10. At the neuropsychological level, there are several domains in which both ASD and ADHD have a pattern of common deficits. These include executive function11, emotion recognition12, affective feedback processing13, as well as sustained attention, and sensory functioning15.Consistent with the hypothesis that both ASD and ADHD depend in part on shared underlying dysfunction, genetic and twin studies show familial associations for both disorders17). Prior evidence has emphasized the importance of the default mode network (DMN) and attention-related macroscopical network as a key to both ADHD and ASD dysfunction20. In a seminal cross-diagnostic neuroimaging study, Di Martino et al.20 examined network centrality metrics in ADHD and ASD patients. Abnormalities were identified in cortical and subcortical areas, some of which were common to both disorders, including the posteromedial cortex. In contrast, some aberrations, such as limbic areas in the bilateral medial temporal lobe, were more closely related to ASD. Moreover, it has been suggested that the salience network (SN) is intimately related to the interplay between the DMN and DAN21, and aberrant coupling patterns between the SN, DMN, and DAN have been reported in both ASD22 and ADHD24.Independent functional magnetic resonance imaging (fMRI) experiments in ADHD or ASD patients have revealed a substantial role of aberrant connectivity in large-scale networks in both disorders (for reviews see refs.8. This intuition is advertised by the Research Domain Criteria (RDoC) initiative of the National Institute of Mental Health25 proposed as an alternative research framework to investigate psychopathological disorders, including ADHD and ASD. Within this framework, mixed dimensional abnormalities of brain circuits are conceptualized as an underlying dysfunction that can contribute to clinically diverging mental disorders to varying degrees27. In the present study, we tested a dimensional view of ADHD and ASD combining resting-state brain connectivity and emerging tools from the machine learning domain. In a transdiagnostic fashion, we hypothesized that brain variation in large-scale network connectivity in the DMN, DAN, and SN can be used to identify shared fundamental network dysfunction in both disorders.The collection of genetic, neuropsychological, and neuroimaging evidence emphasizes the need to understand the common patterns of neural dysfunction that link ADHD and ASD. Both disorders may be best understood from a dimensional point of view with patients who suffer from either disorder located at distant points on a symptom continuumhttp://preprocessed-connectomes-project.org, for in-depth description see refs.29). Particular care has been devoted to help mitigate motion artefacts: Scrubbing30 was used to remove volumes with excessive motion. Rigid-body motion was then estimated within and between runs. The first principal component accounting for 95% of the variance of the six rigid-body motion parameters, as well as their squares was regressed out in nuisance removal. The available pipeline was additionally modified using a standard removal of linear effects with site as a regressor of no interest to control for certain acquisition-related effects.Already preprocessed neuroimaging data were obtained from two large, publicly available datasets: ADHD-200 (http://fcon_1000.projects.nitrc.org/indi/adhd200/) and ABIDE . All data were anonymized, and collected with the approval of the respective ethics boards. Experienced psychiatrists performed patient diagnoses. The ADHD-200 data set provides demographic and clinical information, including age, sex, and measures of symptom severity as assessed by the ADHD rating scale (ADHD-RS). The ABIDE data provide subject information, including age, sex, and measures of symptom severity as assessed by the Autism Diagnostic Observation Schedule (ADOS). Both considered data repositories were preprocessed using the NeuroImaging Analysis Kit  both disorders are more prevalent in males33, and (ii) to exclude gender-specific differences in brain heterogeneity35. Based on these selection criteria, 587 age-matched participants (303 TD) from ADHD-200, and 718 age-matched participants (349 TD) from the ABIDE repository were eligible. This amounted to a total of n = 1305 participants.To help minimize confounding factors, inclusion was restricted to children and adolescents who were male and between 7 to 21 years of age to study the neural mechanism of both disorders during development. Diagnosed and typically developing (TD) participants were age-matched in each dataset : four subregions in the dorsomedial prefrontal cortex (dmPFC), four subregions in the posteromedial cingulate cortex (PMC), and two subregions in the right and left temporoparietal junction (TPJ) were drawn from a recently completed quantitative meta-analytical atlas of the DMN derived by connectivity-based parcellation40. The DMN nodes were supplemented by coordinate-based meta-analyses of closely interacting multi-modal networks , composed of the dorsolateral prefrontal cortex (dlPFC) and intraparietal sulcus (IPS)42. This approach yielded a total of 21 nodes with 210 edges capturing functional network coupling between all possible connectivity pairs. The fMRI signal was summarized by an average time-series for each node, standardized by zero-meaning and unit-variance scaling, and detrended. Pearson’s correlations were then computed between each possible pair of the network nodes. In this way, we effectively reduced each individual’s resting-state whole-brain information to an interpretable set of connectivity variables. In sum, the set of coupling measures reflects each subject’s specific connectivity profile—analogous to a fingerprint of brain network connectivity. Constructing analogous connectivity variables from networks in the Yeo atlas43—without DMN, DAN, and SN—yielded only 52.65% accuracy in the autism-health distinction and 56.06% accuracy in the ADHD sample ).For each participant, the preprocessed resting-state connectivity was summarized in network-coupling statistics. We examined several subregions des Fig.  as used rks Fig. : the sal27. In the following, we will now describe step-by-step what key advantages the applied framework offers.In this study, we devised an innovative hierarchical Bayesian modeling strategy Fig.  to addreIndian Buffet Processes (IBP)44 to allow for the derivation of the relative contributions of hidden properties in the connectivity profiles across all participants. Rather than extracting a pre-specified number of components, as commonly used in principal or independent component analysis, IBP enables formal inference on the number of unknown components. This non-parametric model hence automatically determines the number of underlying components flexibly adapted to the richness of the available directional functional-connectivity data. Additionally, IBP does not perform hard assignments; instead it associates hidden properties to patterns of continuous variation in particular node–node couplings rather than to binary differences.In a first step, we wanted to identify the hidden components of disease variability underlying the connectivity profiles. The challenges implicated are to do so in a data-led fashion, imposing minimal constraints (such as selecting a pre-specified number of components), and to allow for the contribution of multiple shared components at the same time. In an early application in neuroimaging, we used Latent Dirichlet Allocation (LDA)45 we imposed a hierarchy of pre-specified k number of factors onto the connectivity fingerprints based on their association with the hidden properties. In previous research, LDA was successfully applied after engineering structural brain data into positive integers46. But LDA alone is not suited to handling negative-valued, non-discrete input, such as connectivity strengths. Here, the realized combination of IBP and LDA modeling naturally suggests itself because IBP can seamlessly transform the continuous information encoded in the individual connectional fingerprints into discrete, positive-valued vectors indicating the assignment to the underlying hidden properties. For ease of interpretation, LDA then reduced the obtained set of assignments to hidden properties into a small set of overarching connectivity archetypes . A key advantage of combining IBP and LDA is that it enables us to derive hidden sources of variation with mixed memberships. This avoids the necessity of assigning a connectional fingerprint of a participant to only one factor. Instead, each particular individual’s connectional fingerprint could hence be modeled as being generated by k factors  simultaneously.The identified hidden properties in functional network coupling then provided the basis for drawing inference of coherent group-overarching structure  by means of Bayesian hierarchical modeling. Using pre-validation47, to the neuroimaging domain. As a variant of cross-validation, pre-validation was applied to obtain a fairer evaluation of the group labels48. While cross-validation yields reasonably unbiased estimates of the model’s expected error rate in other observations, pre-validation produces a new set of unbiased data or labels that mimic the model performance in later recruited subjects labeled as patients and controls49. These authors emphasize that the key feature of pre-validation is that each label is derived from the entire data set and independently of its response value. Therefore, each label can be treated as if it was derived from a data set completely separate from the test-data. The biological group labels hence are statistically independent from the information encoded in the connectional fingerprints51, and act as if they were derived from separate data.We generated an unbiased set of new labels indicating an assignment to a ‘neurobiological group’ based on the dimensional factors constituting the brain phenotypes for all individuals. To avoid circularity, we translated a statistical modeling scheme, called m = 10 pseudo-randomized splits to ensure balanced groups in both training and test set. The biological labels for all individuals in a given m-th data split were generated by fitting an LDA model on combined brain data from the nine remaining data splits and used to infer factor weights for all observations of the m-th data split. In each m-th data split, pre-validated biological labels were hence estimated by LDA  without access to any actual clinical labels (TD versus ADHD versus ASD) or any brain data from the held-out m-th data split. This procedure generated a new set of labels that was then used to evaluate the out-of-sample prediction of the groups based on a linear classification algorithm . The biological labels were tested for diagnostic relevance based on linear SVMs  by training on each combination of m−1 training data splits and testing on the respective remaining test-data split.We divided the data into 27. After automatic extraction of distinct variability components in DMN coupling , we inferred a hierarchy of sources of variation  that compile the variability in network connectivity of the DMN in TD and diagnosed participants.A hierarchical Bayesian approach was used to identify distinct patterns of DMN coupling with other large-scale brain networks. These functional network patterns were consistently expressed in each of the 1305 TD, ADHD, and ASD individuals from two multisite repositories . The applied transdiagnostic modeling strategy reflects the premise that different biological phenotypes contribute to clinically diverging mental disorders to varying degrees45 hidden properties as the number of components adapted to the complexity of the underlying the available data. We then investigate whether distinct disorder-specific clusters would emerge. However, while every hidden property was observed to be present to different extents in each diagnostic group, no property was found to be uniquely associated with only one group  they belonged to. The applied non-parametric model automatically determined oup Fig. . Togethek factors. In the k = 2 solution, the underlying factors were only related in opposite directions and were hence not able to capture subtle effects in overall network coupling. In wanting to choose the lowest yet most informative number of hidden factors, we favored a solution with k = 3 factors. Hypothetically, if the three clinical groups were to be neurobiologically consistent, three learned LDA components would suffice to describe the underlying dysfunctional pattern. For instance, LDA factor 1 could be related to healthy subjects, LDA factor 2 to ADHD, and factor 3 to ASD. However, following the shared hidden properties, we found that the three factors did not align in a one-on-one fashion with the clinical groups  and hyperactivity/impulsivity , as well as a negative association with performance, verbal, and total IQ scores . In contrast, factor 2 showed the highest associations with ASD diagnosis , and positive associations with verbal and total IQ , as well as negative associations with ADHD diagnosis  and hyperactivity/impulsivity . Factor 3 did not show significant associations with any behavioral items.We then examined the subject-by-subject expression of the imaging-derived endo-phenotypes  in regard to the clinical questionnaires and assessments available from the ADHD-200 and ABIDE repositories. The subject-by-subject expression of factor 1 showed the highest positive associations with ADHD symptom measures, including the level of inattention . Predicting the original categorical diagnoses provided by board-certified psychiatrists achieved only an accuracy of 46.73 ± 3.97% in new participants. This difference in classification accuracy across predictions was statistically significant at p < 0.0001 as evaluated by a t-test. This finding indicates that the imaging-derived neurobiological labels captured the underlying variation of disease dimension within the connectivity information more accurately than the original categorical group labels.(1) We asked whether the new data-derived neurobiological labels capture the neural dysfunction encoded in the connectional fingerprints more accurately than the categorical labels  Fig. . We woulp = 0.73). However, notably, the prediction model improved according to another clinically relevant performance metric: The variance of the prediction model was reduced by a factor of 2. This finding indicated that aiding the prediction model based on categorical group labels by adding information on the biological groups did not enhance categorizing the shared neuropathology reflected in the sets of connectivity features on average across predictions, but made prediction in a given individual more reliable.(2) We explored whether the categorical diagnostic labels could be better predicted from the individual connectional fingerprint  if the factor weights were added to the explanatory variables Fig. . We hencp = 0.47). To emphasize the importance of this finding: Reducing the 210 node–node connectivity features to three indicators of biological phenotypes in each individual still allowed for classification of TD, ADHD, and autistic participants with essentially identical predictive performance.(3) We compared the predictability of the categorical labels based on the full connectional fingerprint with the predictability based on the three factor weights alone , we hypothesized that distinct neural signatures  can be found to describe the common underlying brain network dysfunction. We introduced a novel framework of hierarchical Bayesian inference to identify brain phenotypes of DMN coupling, which were gradually shared across 1305 TD, ADHD, and ASD individuals. We showed that both disorders could be situated along three dimensions of neurobiological variation. We decided to focus our study on previous empirical evidence for shared abnormal large-scale network function in ADHD and ASD. The present data hence suggest that the clinical overlap seen in ADHD and ASD is caused by a shared underlying pattern of brain network dysfunction characterized by distinct coupling patterns of the temporoparietal cortices in the DMN with the DAN and SN. In the following, we discuss the coupling patterns of each factor in the light of the current neuroimaging literature.52. Our results are consistent with reports of decreased connectivity within the DMN and DAN in ADHD populations23, which the investigators proposed to explain attention deficits. In contrast to the behavioral associations of factor 1, the subject-specific expression of factor 2 was positively correlated with ASD diagnosis. On a network level, factor 2 showed high negative functional connectivity for DMN-DAN, low DMN-SN and AI-AM connections. This confirmed and expanded previous findings of observed hypo-connectivity within the salience network itself and between the SN and DMN in ASD53. The aberrant DMN-SN interaction might potentially be the origin of deficits seen in ASD regarding impaired emotional awareness of the self and others, and impaired reorienting to salient social or emotional stimuli.Factor 1 was characterized by high DMN-DAN, medium DMN-SN, low intra-DMN, and low intra-DAN coupling weights. The subject-by-subject expression of this factor showed the highest positive associations with ADHD symptom measures. These observations largely confirm previous findings that the manifestation of ADHD symptoms involves altered DMN-DAN interactions, e.g. as implicated in attentional lapses54: While the anterior subregion was shown to be closely related to the reorientation of attention, the posterior cluster was functionally associated with Theory-of-Mind and social cognition. Across brain phenotypes, distinct patterns of dysconnectivity in the rTPJ effectively differentiated between ADHD and ASD. We hence suggest that a shared expression of factors 2 and 3 may play a critical role in contributing to the variability of shared deficits seen in both disorders.Finally, factor 3 showed negative coupling relations among the DMN and between DAN nodes. In particular, the posterior subregion of the right TPJ depicted lower functional coupling than the anterior subregion, while no such dissociation was observed in the left TPJ. In contrast, factor 2 showed the inverse coupling pattern, while overall showing more positive associations with ASD than ADHD. Earlier studies found a functional separation of the anterior and posterior rTPJ55. ASD, in turn, was reported to show aberrant intra-DMN coupling and diminished antagonistic correlation with task-positive networks, such as DAN and SN57. However, dedicated translational research will be needed to extend the search for transdiagnostic biomarkers and eventually evaluate their potential use in treatment.Connectivity-derived biomarkers anchored in the partly shared functional architecture of the DMN may further disentangle the observed heterogeneity in ADHD and ASD diagnostics and potentially lead to targeted treatment options in the future. In ADHD, Peterson and colleagues specifically reported that psychostimulants may improve ADHD related symptoms by normalizing dysfunctional connections between DMN and DAN related activity in adolescents58 but also individual treatment response, similar to recent work in depression59. Identifying and validating brain-based endo-phenotypes will most likely be and continue to be an unavoidable cornerstone for personalized medicine in child psychiatry60 and general psychiatry61.In conclusion, we used an innovative hierarchical Bayesian modeling strategy to identify and formalize intermediate brain phenotypes to interrogate our hypothesis of shared dysfunctional connectivity in the DMN, DAN, and SN. The endo-phenotypes derived in a data-driven fashion without access to any clinical or diagnostic information were gradually shared across the neurodevelopmental disorders of ADHD and ASD. We demonstrated that hundreds of resting-state brain scans for each participant could be re-expressed in only three numbers that captured hidden heterogeneity in DMN coupling. The derived brain endo-phenotypes were then demonstrated to enhance categorical diagnoses made by board-certified psychiatrists to capture the neural dysfunction shared in both disorders more accurately. The realized analysis strategy is not constrained to ADHD and ASD, but may be applied to a variety of major psychiatric disorders. Further investigations may target not only shared dysfunctionAll used data are open-access (ABIDE and ADHD-200) and are readily accessible to the reader.


Previous studies have suggested a positive association between self-reported maternal acetaminophen use during pregnancy and risk of attention deficit hyperactivity disorder (ADHD) in offspring. We sought to examine the prospective association between maternal plasma biomarkers of acetaminophen intake and ADHD diagnosis in the offspring. This report analyzed 1180 children enrolled at birth and followed prospectively as part of the Boston Birth Cohort, including 188 with ADHD diagnosis based on electronic medical record review. Maternal biomarkers of acetaminophen intake were measured in plasma samples obtained within 1–3 days postpartum. Odds ratios for having ADHD diagnosis or other developmental disorders were estimated using multinomial logistic regression models, adjusting for pertinent covariables. Compared to neurotypical children, we observed significant positive dose-responsive associations with ADHD diagnosis for each maternal acetaminophen biomarker. These dose–responsive associations persisted after adjusting for indication of acetaminophen use and other pertinent covariates; and were specific to ADHD, rather than other neurodevelopmental disorders. In the stratified analyses, differential point estimates of the associations were observed across some strata of covariates. However, these differences were not statistically significant. Maternal acetaminophen biomarkers were specifically associated with increased risk of ADHD diagnosis in offspring. Additional clinical and mechanistic investigations are warranted. Attention deficit hyperactivity disorder (ADHD) is one of the most common lifelong neurodevelopmental disorders in the world. Its prevalence among children ages 4–17 years in the U.S. increased significantly from 7.0% to 10.2% during the past two decades ,13,14,15Since 2013, research studies analyzing five prospective cohorts from Europe and New Zealand have consistently shown a positive association between maternal intake of acetaminophen during pregnancy and increased risk of ADHD and its related symptoms in offspring ,39,40,41In this study, using the data from the Boston Birth Cohort, we sought to examine the prospective association between maternal plasma acetaminophen metabolites levels measured within a few days after delivery and ADHD diagnosis in the offspring. Given the timing of our biomarker measurement, we are poised to address a specific question that has not been explored in the previous study: Is the maternal use of acetaminophen during peripartum period (as reflected in plasma biomarker levels) associated with increased risk of ADHD diagnosis in offspring?Initiated in 1998, mother/infant pairs were recruited at birth from the Boston Medical Center (BMC) for participation in the Boston Birth Cohort (BBC) ,45. The As illustrated in the study flowchart, of the 3098 children in the postnatal follow-up study in the BBC, 1412 mothers had sufficient plasma samples for metabolomic assay. Of the mothers with metabolomic data, we further excluded 232 participants who had missing data for key covariates. Our final sample comprised 1180 mother/infant pairs with all pertinent data: exposure, outcome, and covariates . AlthougWe extracted information regarding each child’s neuro-developmental diagnoses as documented in their electronic medical records (EMRs). Beginning in 2003, BMC implemented EMR as part of routine data collection for both well-child and specialty clinical visits. The primary and secondary diagnoses for each clinical visit were coded in the EMR using the International Classification of Diseases, Ninth Revision (ICD-9) (before 1 October 2015) and ICD-10 (after 1 October 2015). Thus, all children in the BBC postnatal follow-up study with a related ICD-9  or ICD-10  code included in their EMR between 2003 and 2016 were classified as having ADHD. Similarly, children with an ICD-9  or ICD-10  code were classified as having an autism spectrum disorder (ASD). Furthermore, children with any of following developmental disorder diagnoses noted in their EMR were classified as having other developmental disorders (other DD): developmental delays, or intellectual disabilities. Children without any diagnosis of ASD, ADHD, developmental delays, or intellectual disabilities were classified as neurotypical (NT). N-Acetyl-l-cystein-S-yl) acetaminophen [N-Acetyl-l-cystein-S-yl) acetaminophen in maternal blood was measured using liquid chromatography-tandem mass spectrometry (LC-MS) techniques at the MIT Broad Institute Metabolite Profiling Laboratory. All the intensity levels were inverse normal transformed for the subsequent statistical analyses.Maternal plasma biomarkers of acetaminophen use were measured using nonfasting blood samples obtained within 1–3 days postpartum. As illustrated in minophen . The peaBased on previous literature ,39,40,412 tests for categorical variables. The main exposures analyzed in this study were maternal acetaminophen metabolite levels, which were inverse normal transformed to approximate the normal distribution. The inverse normal transformed unchanged acetaminophen levels were also categorized into tertiles. Due to the high rate of non-detection, the inverse normal transformed acetaminophen glucuronide and 3-(N-Acetyl-l-cystein-S-yl) acetaminophen levels were categorized into three groups: no detection, below median, above median of detected values. Based on previous findings regarding the proportions of acetaminophen metabolites typically found in blood samples [N-Acetyl-l-cystein-S-yl) acetaminophen/5%)/60%) [The characteristics of the study sample for the ADHD, ASD (excluding participants with ADHD diagnosis), other DD, and NT groups were compared using one-way ANOVA for continuous variables and χ samples , we furt5%)/60%) . The ace5%)/60%) . Materna5%)/60%) .psmatch2 package. We further repeated the sequential models for each of the following outcomes: “ADHD only” (excluding ASD diagnosis), “ASD only” (excluding ADHD diagnosis), and “ADHD and ASD” (having both diagnoses), all compared to the NT group. STATA® version 14.0 software was used to perform all analyses .We conducted sequential multinomial logistic regression models to examine the association between maternal acetaminophen metabolite levels and the risk of having ADHD diagnosis, ASD diagnosis (excluding ADHD diagnosis), or other DD diagnosis in offspring. Multinomial logistic regression is a method that generalizes logistic regression to the tests with more than two possible discrete outcomes . Except In the final sample, there were 188 children with a diagnosis of ADHD, 44 children with a diagnosis of ASD (without ADHD diagnosis), 344 children with a diagnosis of other DD, and 604 NT children. The median age at first ADHD diagnosis was 7 years. We also explored if the associations between acetaminophen metabolites and ADHD varied by strata of covariables. In this prospective birth cohort study, we found a significant positive association between maternal blood acetaminophen metabolite levels measured within 1–3 days postpartum and ADHD diagnosis in offspring; such an association was not observed for other developmental disorders. This association remained even after adjusting for indication factors of acetaminophen use  and other pertinent covariates. This study has contributed the following new information to the field.Even though positive associations between maternal reported intake of acetaminophen during pregnancy and risk of ADHD diagnosis in their offspring have been reported by multiple independent large cohort studies ,39,40,41To our knowledge, this is the first prospective birth cohort study to examine the association between objective maternal plasma biomarkers of acetaminophen and offspring ADHD diagnosis, and to take into account a large number of potential covariables. Our study was further strengthened by the diagnosis of ADHD by both general pediatricians and developmental specialists. By demonstrating a prospective and dose–response relationship using biomarkers specific to acetaminophen intake during early postpartum, our study findings further extend the previously identified positive association between acetaminophen and ADHD from pregnancy into postpartum.Although the causality and biological mechanisms underlying the maternal acetaminophen and child ADHD association remain to be determined, the potential for neurotoxicity is plausible according to previous findings. First, the therapeutic effect of acetaminophen inhibits prostaglandin production . ProstagWhile tests of interaction were not significant (likely due to lack of power), our stratified analyses identified multiple maternal and fetal factors that may enhance the association between maternal acetaminophen metabolites and ADHD diagnosis in offspring. These potential effect modifiers are biologically plausible and warrant further investigations. For instance, we found that the effect size of acetaminophen use on the risk of ADHD diagnosis is more pronounced among women who drank alcohol six months before or during pregnancy. Effect modification by alcohol is supported by biological studies ,63. A meOur study also had some limitations. First, this study only included a one-time measurement of maternal acetaminophen metabolite levels within 1–3 days postpartum. Acetaminophen has a 2–3 h half-life in adults , thus thMaternal plasma biomarkers of acetaminophen use measured within a few days after delivery were specifically associated with increased risk of ADHD diagnosis in offspring, not with other developmental disorders. This association remained after adjusting for multiple previously identified potential confounders and potential indications for acetaminophen use. While our study provides the first objective biomarker evidence of the relationship between maternal acetaminophen use and ADHD diagnosis in offspring, we could not provide definitive support for a causal inference of this relationship, given the observational nature of this study and the limitations outlined above. However, our evidence drawn from the perinatal period lends further support for the association between maternal acetaminophen use and ADHD in offspring, which has been illustrated by multiple large studies of acetaminophen use during pregnancy via self-reported information. If further confirmed, these results may help address concerns raised by the Society for Maternal-Fetal Medicine and the U.S. Food and Drug Administration ,43. Taki


Attention deficit hyperactivity disorder (ADHD) is recognized as the most common, and most studied, developmental age disorder. Basic information, such as the most appropriate case definition and the best way to evaluate the disorder’s prevalence rate, however, remains an open issue.A comprehensive meta-analysis on the epidemiology of ADHD in Italy, which was lacking from the literature, was therefore performed to attempt to estimate the actual prevalence rate of ADHD, highlighting conceptual and quantitative differences between clinical-diagnosis and survey-based symptoms studies. The Medline, Embase, and PsycINFO databases, and the grey literature, were searched up to January 2018. The review was laid out in three main sections: an overall prevalence estimate, an epidemiological profile of ADHD symptoms, and an attempt to define the actual rate of ADHD diagnosis, as emerged from Italian studies.A total of 15 unique studies were included. These contributed to estimating the prevalence of ADHD in 67,838 subjects aged 5–17, representing 9 of the 20 regions (45%) of Italy. Overall, the pooled prevalence of ADHD was 2.9% (range: 1.1–16.7%). When distinguishing studies based on case definition, however, we found an average prevalence estimate, based on symptoms criteria, of 5.9% (range: 1.4 to 16.7%) and a best-estimate prevalence rate of 1.4% (range: 1.1 to 3.1%).Following the case definition for epidemiological studies of ADHD, counting only subjects with an ADHD diagnosis performed and confirmed by clinical assessment would reduce the wide variability in prevalence estimates, and, above all, would both describe the real rate of subjects suffering from ADHD disorder and avoid misdiagnosis. The exact time of onset for individual cases in psychiatry is often not known, and prevalence estimates on a given period are used as a substitute for identifying the proportion of cases of a particular disorder in a defined population .Several factors can influence observed prevalence rates as the diagnostic criteria, the setting, the population studied, the type and severity of the disorder, and the comorbidities. Since measures of prevalence are also helpful in assessing health care needs and in planning health care services , estimatTo date, ADHD is considered the most common, and most studied, developmental age disorder, even though basic information, such as the most appropriate case definition for estimating its prevalence rate, remains an open issue and leaves room for significant, debates in scientific literature , 7. The ADHD is recognized as a difficult diagnosis to make accurately, not only because of the many comorbid conditions, but also for the low specificity of the core symptoms: the list of disorders or conditions that can make a child appear restless or distractible is almost endless. Making a proper diagnosis thus requires a detailed evaluation of development, educational demands, and what is expected of the child in a given circumstance and at a given time, as well as symptomatology, impairment, and risk , 18.Although it is widely recognized that several ADHD symptoms, as investigated by symptom surveys or interviews, may occur as manifestations of other medical (i.e. hypoglycemia or sensory processing disorders) and psychiatric  disorders, few published studies have directly examined the rate and type of psychiatric and medical disorders in those previously identified as ADHD positive by teacher or parent ratings . All psyIn such a context the goal of this study was to evaluate certain factors that can affect the prevalence of ADHD in reported studies and, consequently, the observed variability, in particular in overall pooled estimates. We analyzed the methodological approach used, and the implications in practice, of Italian ADHD studies.The research was approved by the Institutional Review Board of the Istituto di Ricerche Farmacologiche Mario Negri IRCCS.We searched the Medline, Embase, and PsycINFO databases for articles written in English and published before January 2018 using the following Medical Subject Headings and free text terms: “ADHD”, “ADD”, “attention deficit”, “attention deficit hyperactivity disorder”, “hyperkinetic disorder”, “epidemiology”, “prevalence”, “survey”, “child*”, and “adolesc*”. Studies with an Italian affiliation and point prevalence estimates of ADHD in Italy were extracted. Non indexed journals were searched for in the Google Scholar search engine by using keywords to identify potentially eligible studies. Articles written in Italian were also considered. Additionally, the reference lists of all eligible articles were scanned, as well as key Italian journals and websites, to identify additional, potentially relevant papers. Studies considered eligible were those that used the diagnostic criteria or survey instruments based on DSM-III, DSM-III-R, DSM-IV, DSM-5, or ICD-10, with samples from community, school, or clinically referred populations. We included studies with participants aged < 18 years.After removing duplicates, the two authors screened the titles and abstracts for adherence to eligibility criteria. In cases of uncertainty concerning eligibility, the records were discussed until a consensus was achieved. For studies deemed suitable, we obtained the full text for data extraction. References of suitable studies were searched to recover any relevant articles.Data were extracted by the authors and involved general publication information, demographic variables of the population sample, year of sampling, setting, frame procedure, region and city, screening and diagnostic instruments used to define a case as ADHD, informant, and whether a clinical impairment evaluation was performed. The authors independently assessed each Italian study for methodological quality. The included articles were assessed by using a modified tool developed by Hoy et al.  for asse2 statistic [z test of 2 proportions to examine differences in prevalence estimates of studies by factors considered. Five studies reported prevalence estimates from different types of informants. These studies were included in univariate and multiple meta-regression analyses and in the overall pooled results for each prevalence estimate.For each retrieved study an assessment of inclusion, exclusion, and quality was performed independently by the two authors, and the inter-reviewer reliability was measured using Cohen’s Kappa statistics. Study data were analysed using Stata version 11.1 . Because of the differences in study sample sizes, SEs of the prevalence estimates from each study were calculated based on the exact binomial likelihood. Summary effect estimates of prevalence were calculated by using a random effects meta-regression model because there was a clear heterogeneity between the studies tested using the Itatistic . The stutatistic . Study fn = 12), while the rest were performed in clinical settings (2 in child and adolescent neuropsychiatric services and 1 in family paediatrician practices), using a whole population approach. Three of the school-based studies also involved child and adolescent neuropsychiatric services in the clinical confirmation of suspect ADHD. Overall, the methods used in the studies were rating scales, questionnaires, interviews, or other clinical tools based mainly on DSM-IV criteria (11 studies), while the remaining were conducted according to DSM-III-R (2 studies), DSM-III (1 study) and ICD-10 (1 study) criteria. The informants in the studies were teachers in 11 cases, patients in 1, and parents in 3; 2 studies included both teachers and parents.Our search yielded 199 citations, 5 of which were duplicates . No studies met all 8 criteria, although 93% had a low, or moderate, risk of bias. The majority of studies rated poorly for the representativeness of sample (87%).n = 22), was 4.3% , with a wide inter-study range of 1.1 to 16.7% . Only 2 studies required an individual to meet symptom criteria based on both parent and teacher ratings, using the “AND rule” algorithm that codes as positive only if both rates agree. Finally, 6 of 15 studies (40%) used a best estimate diagnostic algorithm in which a clinical evaluation was performed at the end of the assessment to obtain an ADHD diagnosis based on standard classification criteria . Four of these 6 studies assessed a population sample and 2 a population of clinically referred subjects.Within the univariate models, prevalence estimates for ADHD were, on average, 1.7% lower when DSM-IV criteria were used than when other criteria were used Table . One stuAccording to both the clinical and methodological diversity of the retrieved studies, all univariate analyses revealed that all considered covariates were significantly associated with heterogeneity of prevalence estimates.After entering all study factors into a multivariate meta-regression, only teacher and child case definition remained significant Table .Performing a clinical assessment to make a diagnosis in mental health care is necessary to define whether a subject suffers from a psychiatric disorder or not. In our opinion, therefore, selecting an appropriate case definition that is supported by a clinician-based diagnosis is a critical step to estimating the real prevalence rate of ADHD.This opinion is not entirely new: 20 years ago, Swanson et al.  clearly We performed a systematic evaluation of the rate of ADHD children and adolescents in Italy with the overall aim to distinguish studies estimating ADHD prevalence based only on symptom-surveys from studies providing a clinically comprehensive evaluation. We also aimed to provide an overall ADHD estimate, as done in previous reviews. The first rate we computed was the overall Italian prevalence of ADHD, found considering all types of samples with different case definition methodologies. As expected, considering Italy’s ADHD history – characterized by a predominantly psychodynamic-psychoanalytic approach  – the ovThe first population (ADHD symptom rate) is the number of subjects presenting ADHD symptoms who could have an ADHD disorder or another psychiatric or medical disorder with similar clinical manifestations. This population is often recognized through symptom surveys compiled by parents or teachers, and needs a clinical evaluation to confirm whether ADHD is actually present. This population therefore represents the number of children and adolescents with behavioral symptoms of ADHD who need a specific evaluation by a specialist service/clinician.From our findings, this population in Italy, calculated from studies with data rates based on only symptom-surveys, consists of about 439,000 subjects  among children and adolescents aged 5 to 17 years of the Italian paediatric population. This is, from a health care point of view, the population of subjects who need a psychiatric evaluation. This rate, based on symptom-surveys, differs from that found with the same methodological approach in Thomas and colleagues’ review (5.9 vs. 13%) , as wellThe second rate, the prevalence of ADHD diagnosis, is, according to us, the real rate of ADHD prevalence and refers to the number of patients presenting ADHD symptoms who have an ADHD diagnosis confirmed by a clinical evaluation. This population, similarly to the previous one, can be recognized through symptom surveys compiled by parents or teachers, but has an ADHD diagnosis and evaluation that confirm the presence of ADHD. This second population represents the number of children and adolescents with an ADHD diagnosis who need a specific treatment for ADHD.From our findings, in Italy this population (ADHD diagnosis), calculated from studies including only patients with an ADHD diagnosis confirmed by clinical evaluation, consists of about 105,000 subjects  among the Italian paediatric population aged 5 to 17 years. From a health care point of view, this is the population of patients who need treatment. In line with previous comments, only a few review studies calculated the prevalence of ADHD diagnosis separately from the overall rate. It is even more important to keep in mind the distinction between diagnostic procedures if we consider that our findings  differ from those of Willcutt   and the ADHD diagnosis prevalence , when diagnostic case definition based on clinical evaluation is used, comparisons of the range rates suggest that the differences between these homogenous types of studies are small, and, thus, in our opinion, more accurate.Results should be interpreted in the context of two main limitations. First, the number of studies included is small and the methodological approach is heterogeneous so the findings that emerged may not be similar to those of other contexts or countries. Second, although this is the first study analyzing the overall ADHD prevalence in Italy, all data originate from a single country. This may affect the comparability of the reported findings and the generalization of the results to a worldwide scenario would therefore be inappropriate.Epidemiological studies concerning ADHD need more efforts to identify the cases, to assess the prevalence, and to use administrative databases as provided by the American Agency for Healthcare Research and Quality (AHRQ) . In our Mental health is certainly a public health issue, and many disorders arise in childhood. To support the promotion of mental wellbeing and the primary prevention of psychiatric condition  knowledg