Preterm survivors from the neonatal intensive care unit (NICU) are considered to be at risk for some neurobehavioral disorders such as attention-deficit/hyperactivity disorder (ADHD). The current study aimed to explore the relationship between ADHD and premature infants in Taiwan.A total of 195 children  diagnosed with ADHD based on DSM-IV and aged between 6 to 12 years and a control group of 212  age- and sex-matched healthy children were enrolled. The ADHD-Rating scale and CGI severity were performed by child psychiatrists. Demographic data of the children, including birth history, perinatal neurological and respiratory problems were collected to facilitate the investigation of whether a correlation exists between ADHD and prematurity.P = 0.003). Pearson correlation showed a significantly negative correlation between gestational age and ADHD-RS score, inattentive score, hyperactivity and CGI-S score . However, only a CGI-S score (P = 0.018) showed a significantly correlation between low birth weight and ADHD.The ADHD group had a significantly higher rate of prematurity and significantly higher rate of low birth body weight (defined as <2500 g) than the control group (both Premature infants have significantly more severe symptoms of ADHD at school age and they were highly correlated. Further study is necessary to determine the main effect and pathogenesis of moderate as well as extreme preterm birth on the development of ADHD. Attention-deficit hyperactivity disorder (ADHD), a neurobehavioral syndrome characterized by inattention, impulsivity and hyperactivity, has been described for over a century as an unruly behavioral disorder most commonly seen in boys . ADHD isThere is growing interest in the mental health of premature infants, partly because their mortality rate has decreased over the last two decades ,11 and m. All patients were diagnosed by expert child psychiatrists and fulfilled the criteria of ADHD according to the 2000 DSM-IV-TR [We reviewed the medical records of all children diagnosed with ADHD between January 2001 and December 2009 in the Department of Pediatric Psychiatry of Chang Gung Children’s Hospital (CGMH), a tertiary-level university-affiliated teaching hospital in northern Taiwan. This study was approved by the institutional review board of CGMHSM-IV-TR . ChildreSM-IV-TR  and thosA group of children involved in the study as the controls were recruited from the general community, and didn’t have any major physical diseases, neurological problems, or psychiatric illnesses. We planned to enroll a group of age and sex-matched children to our ADHD group. An informed consent was obtained from their parents after well explanation. During this study period, 195 ADHD children  who were diagnosed based on DSM-IV-TR were enrolled. The control group consisted of 212 age- and sex-matched children . There was no significant difference between the basic demographic data of the study and control groups  , which it-test. Logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CI) for risk of developing ADHD with prematurity and low birth weight. Multivariate logistic regression was performed to adjust for covariates of gender and age. Three kinds of model were tested by simple and multiple regressions. Model 1a, 1b, 1c, 1d analyze the effects of preterm on total score of ADHA, ADHD inattention score, ADHD hyperactivity score and CGI-S scores. Model 2a, 2b, 2c, 2d test the impacts of preterm and LBBW on total score of ADHA, ADHD inattention score, ADHD hyperactivity score and CGI-S scores. For Model 3a, 3b, 3c, 3d, gender and age were added into Model 2a, 2b, 2c, 2d as covariates to control the effects of these two variables. All statistics were performed using the commercially available software SPSS software for Windows , and a P value of less than 0.05 (two-tailed) was considered to be statistically significant.We defined prematurity as a child who was delivered before 37 weeks’ gestation and low birth body weight as < 2500 g. The chi-square test and Fischer’s exact test were used for categorical data, and comparisons of the continuous data between groups were performed by the student’s P = 0.003). The body mass index and rate of respiratory complications or neurological complications at birth were not significantly different between these two groups. The severity of ADHD symptoms, judged by ADHD-RS-IV and CGI-S scores, was significantly more severe in the ADHD group than the control group .During the study period, a total of 195 children  diagnosed with ADHD based on DSM-IV-TR were enrolled and completed the whole assessments. A control group of 212 age- and sex-matched children  were recruited from the surrounding schools in the community. The demographic data, including birth history, are summarized in Tables Tables P = 0.018), but was not significantly correlated with hyperactivity score. Moreover, a lower birth body weight was also found to correlate with a higher ADHD RS total (P = 0.057) and inattention (P = 0.053).Tables Our study found that the ADHD group has a relatively higher rate of prematurity and a significantly higher rate of low birth body weight than the general population. We also demonstrated that both moderate preterm birth  and low birth body weight (defined as birth body weight < 2500 g) are associated with more severe ADHD symptoms. Previous studies have concluded that very preterm children were reported to exhibit significantly more behavioral problems and cognitive disorders ,24; howeThe significant association between ADHD and preterm birth or low birth body weight can be explained by several mechanisms. First, some of the children suffered from intrauterine growth retardation and their less matured brain structure due to suboptimal fetal environment; these conditions may be associated with postnatal illness and later development of ADHD . Second,Another interesting finding of our study was that the more severe ADHD symptoms, including inattention, hyperactivity and impulsivity, were significantly correlated with more preterm birth or lower gestational age. However, lower birth body weight was only associated with inattention, but not hyperactivity or impulsivity. To our knowledge, our study was the only one to conclude both low birth body weight and preterm birth as independent risk factors for the development of ADHD at school age. These two factors may not be correlated, because in studies of low-birth-weight (<2500 g) but term-born children, small body size at birth predicts behavioral symptoms of ADHD ,31. ThesPrevious studies have demonstrated an increased risk for ADHD in follow-up studies of preterm survivors from NICUs -34. EvenA major limitation of our study is its relatively small sample size and retrospective design. We are unable to further extend our conclusion to very low birth body weight children (< or = 1500 g) and very preterm children (< or = 32 weeks’ gestation). However, our study had excluded the cases of well-defined brain damage such as intraventricular hemorrhage, periventricular leukomalacia, or cerebral palsy from perinatal asphyxia. We also excluded children with an IQ of less than 70 on the WISC-III, and those with major mental, neurological, or physical disease, which may have resulted in the exclusion of very low birth body weight and very preterm infants from our study sample. Furthermore, our study applied ADHD questionnaires from parents and teachers rather than utilizing objective measurements of quality of life, person-to-person relationships, academic achievements, or neurocognitive tests. A further well-designed, prospective study is required to confirm our findings.It is our hope that, by gaining a better understanding of the strong relationships between preterm birth, low birth body weight and the risk of developing ADHD, many undefined efforts can be progressed to avoid preterm birth. Further attention should be paid to these children by having child psychiatric clinics perform regular follow-ups to track their behavioral and emotional conditions.Children with ADHD have a significantly higher rate of prematurity and low birth body weight. The severity of ADHD symptoms, including ADHD RS total score, inattention or hyperactivity scores and ADHD CGI-S scores, are highly correlated with extent of prematurity. Premature brain, less favorable postnatal condition and illness of preterm neonates, or poor parent-child interaction may contribute interactively to their suboptimal neurobehavioral development and subsequent ADHD, but the underlying pathogenesis remains uninvestigated and deserves further studies.The authors declare that they have no competing interests.S-MC Carried out the study and wrote the manuscript. M-HT collected the data; assumed the role of attending physician of the premature neonates. J-FH Responsible for editing the English version of the study; assumed the role of attending physician of the premature neonates. F-MH performed the statistical analysis. H-RH the attending physician of our premature neonates. Y-SH the corresponding author, overview and supervise the whole study and writing of manuscript. All authors read and approved the final manuscript.The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-244X/12/85/prepub


N = 711). Regression analyses were used to examine association of SCQ scores with core ADHD features, clinical comorbidities and cognitive and developmental features, with adjustment for putative confounders. For outcomes showing association with total SCQ score, secondary analyses determined levels of differential association of the three ASD sub-domains. Results suggest that increasing ASD symptomatology within ADHD is associated with a more severe phenotype in terms of oppositional, conduct and anxiety symptoms, lower full-scale IQ, working memory deficits and general motor problems. These associations persisted after accounting for ADHD severity, suggesting that autistic symptomatology independently indexes the severity of comorbid impairments in the context of ADHD. Sub-domain scores did not show unique contributions to most outcomes, except that social deficits were independently associated with oppositional symptoms and repetitive behaviours independently predicted hyperactive-impulsive symptoms and motor problems. It would be worthwhile for clinicians to consider levels of socio-communicative and repetitive traits in those with ADHD who do not meet diagnostic criteria for ASD, as they index higher levels of phenotypic complexity, which may have implications for efficacy of interventions.Traits of autistic spectrum disorders (ASD) occur frequently in attention deficit hyperactivity disorder (ADHD), but the significance of their presence in terms of phenotype and underlying neurobiology is not properly understood. This analysis aimed to determine whether higher levels of autistic traits, as measured by the Social Communication Questionnaire (SCQ), index a more severe presentation in a large, rigorously phenotyped sample of children with ADHD (The online version of this article (doi:10.1007/s00787-013-0398-6) contains supplementary material, which is available to authorized users. Autistic spectrum disorders (ASD) and attention deficit hyperactivity disorder (ADHD) are childhood-onset neurodevelopmental disorders. Although there are some important differences , ASD and ADHD share many similar impairments in developmental and cognitive domains. Both are substantially more common in boys than girls, with a gender ratio of around 6:1 . There iImportantly, ASD and ADHD also show remarkably high comorbidity with each other, at trait and full disorder level, both in clinical –19 and gCurrent diagnostic classification systems (DSM-IV and ICD-10) preclude the co-diagnosis of ADHD in children with ASD. However, with comorbidity estimates being so high, the DSM-5 will no longer have this restriction . In viewThe profile of ADHD symptoms in children with a primary diagnosis of ADHD does not appear to be influenced by the presence of high ASD traits , 29. HowResearch on comorbid psychopathology differences in children with ADHD with high vs. low levels of ASD traits is also mixed. One study found no clear differences , whereasIn terms of general cognitive ability, the presence of ASD traits in children with ADHD does not appear to be associated with IQ , 32. HowAlthough in summary, there are a number of studies beginning to address whether autistic traits in children with ADHD index a more severe clinical, cognitive and developmental profile –32, inteBased on previous literature, we hypothesise that the presence of an increasing number of ASD symptoms in those with ADHD may be associated with combined subtype ADHD diagnosis, a greater number of ADHD symptoms, more severe comorbid anxiety, depression, ODD and CD problems, lower IQ, lower reading ability, more EF problems and a greater rate of speech and motor problems. Although traditionally regarded as clustering very strongly, the three domains of ASD  have been suggested to dissociate, both in terms of clinical presentation and in terms of underlying genetic aetiology . As a seChildren with a confirmed or suspected clinical diagnosis of ADHD were recruited through child psychiatry and paediatric outpatient clinics in the United Kingdom for a study of genetic and environmental influences on ADHD. Approval for the study was obtained from the North West England and Wales Multicentre Research Ethics Committees and written informed consent to participate was obtained from parents, and assent/consent was gained from the children.N = 711 young people included in the analyses. There were 113 females (15.9 %) in the sample and the children were aged between 5 and 18 years .Children were eligible for inclusion in this current analysis if they had a current diagnosis of ADHD DSM-III-R or DSM-IV with complete subtype data available and sufficient ASD trait data for analysis (see “κ = 1.0). Inter-rater reliability for parent-rated CD symptoms was very good (intra class correlation = 0.98). Confirmation of pervasiveness of ADHD symptoms in school was obtained using the Child ADHD Teacher Telephone Interview (CHATTI)  and low family SES . There was no association of SCQ and child’s age at assessment , gender  or parental education .Table Results of regression analyses of SCQ scores with clinical, cognitive and developmental outcomes are displayed in Tables In terms of ADHD profile, higher SCQ scores were associated with presence of the ADHD combined subtype diagnosis in comparison to the other ADHD subtypes in the unadjusted model. SCQ scores were also positively associated with number of inattentive, hyperactive-impulsive symptoms and total number of ADHD symptoms. This pattern of results remained similar after adjusting for covariates.Higher SCQ scores showed association with the presence of ODD and CD diagnoses and increasing ODD and CD symptoms. The pattern of results persisted after adjustment for covariates, though overall the strength of the associations decreased.B = 2.66, p = 6.0 × 10−5) and covert  symptoms independently showed association with SCQ total. After adjusting for covariates, aggressive symptoms continued to show independent association with SCQ scores  but covert symptoms were no longer associated .In the secondary test of CD symptoms, both aggressive . However, there was a trend towards an association between higher SCQ scores and a lower Working Memory Index above and beyond contributions shared with the other three WISC-IV indices .Full-scale IQ was found to be negatively associated with SCQ score. A secondary multivariate regression model was used to explore the relative contributions of the four indices of the WISC-IV to this association. There were no unique contributions of Verbal Comprehension Index, Perceptual Reasoning Index or Processing Speed  and RRBs independently predicted hyperactive-impulsive symptoms , anxiety symptoms  and presence of motor problems . These results are available from the authors upon request.For each of the outcome variables showing a significant association with total SCQ score, additional tests were performed to determine whether any of the three SCQ sub-domains  showed an independent contribution to the observed association. After accounting for multiple testing, the sub-domains were generally not found to contribute independently to the associations seen with the outcome variables. The exceptions to this were that social deficits were independently associated with number of ODD symptoms  are lower than reported in children ascertained primarily in terms of a diagnosis of ASD (mean = 22.3 ), as woup values fell below the threshold accounting for multiple testing, specifically in terms of depression symptoms and ODD and CD diagnoses. The most robust associations were found between SCQ score and ODD, CD and anxiety symptoms, working memory problems and motor problems, which persisted after accounting for ADHD symptoms. These results lend strength to the assertion that autistic symptoms independently drive the observed severity of these comorbid impairments, rather than simply being a proxy marker of ADHD symptom severity.As predicted, the results on the whole suggest that autistic symptomatology, as indexed by total SCQ scores, within ADHD (even when known ASD cases are not included) is associated with a more severe phenotype in terms of several clinical, cognitive and developmental features. The results show that higher SCQ scores predict greater severity of ADHD symptoms and greater likelihood of combined subtype, more comorbid ODD, CD, anxiety and depression symptoms, lower cognitive ability  and a greater rate of general developmental (motor and language) problems. This pattern of results persisted even after taking into account potential confounding effects of age, IQ, gender and family SES and was found not to be driven by severity of ADHD itself. However, when covariates were included some of the associations weakened and Although more working memory deficits were predicted by increasing SCQ score, there was no association detected between SCQ scores and whether children were able to successfully complete the extra-dimensional shift component of the IED CANTAB task, a further EF measure. Although previous studies have shown that unmedicated children with ADHD and children with ASD perform worse on this aspect of the IED task than controls –55, the Secondary analysis of the independent contributions of covert and aggressive CD symptoms to the association between SCQ scores and CD symptoms indicates that it is the aggressive symptoms which drive this association. This finding is in line with previous studies which have shown that CD traits in children with ADHD are a marker of greater clinical severity  and highSecondary analyses were also performed to determine the relative contributions of the three SCQ sub-domains  to observed main associations. Results indicated that for most outcomes associated with SCQ total score, the three sub-domains did not show any independent association above and beyond the variance they explained in common, although with a few exceptions. After correction for multiple testing, associations were observed between the sub-domain of social deficits and number of ODD symptoms, as well as the sub-domain of RRBs and hyperactive-impulsive symptoms, anxiety symptoms and general motor problems. The results suggest that RRBs in children with ADHD, as assessed by the SCQ, may index a more general dysfunction of motor processes . Previous research has shown that all three sub-domains contribute to the higher SCQ scores in children with ADHD when compared to their unaffected siblings and typically developing controls , althougAn alternative approach to investigate the effects of comorbidity between ASD and ADHD is to assess whether a sample of children ascertained primarily in terms of a diagnosis of ASD shows similarly elevated comorbid and cognitive problems. Studies generally find that children with ADHD + ASD have elevated ASD symptomatology, higher rates of comorbid ODD, CD, anxiety and depression problems and lower IQ scores than children with ASD-only –66 althoN = 85) were excluded (results available from first authors).The current study includes the following strengths but also has a number of limitations. The sample size was large and rigorously phenotyped for ADHD and comorbid conditions, using the CAPA for every participant, and a comprehensive assessment of cognition was undertaken. This study assessed ADHD using DSM-IV criteria that require excluding cases of ASD and, therefore, children with comorbid ASD were not included. However, ASD scores were not assessed by standardised interview and observations. Given that children with ADHD and ASD show higher rates of ID, children were not excluded on the basis of IQ so as not to lose clinically valuable information. Likely for historical reasons , childreIt is not clear whether the SCQ has validity for autistic traits in ADHD in the same way that it does in those with ASD and the general population, although that could easily also apply to assessment of other forms of comorbid psychopathology in ADHD . For instance, the item on “complicated movements of the body” (part of the sub-domain of RRBs) may be interpreted as referring to straightforward hyperactivity, an idea that has been proposed by others in general with regard to parental reports of children’s behaviour , 69. An N = 433) to those with SCQ score ≥15 (N = 278) gives the same pattern of results and direction of effects as reported for the continuous analysis (results available from the first authors). Given that a previous study suggested that a cut-off point of 11 is particularly meaningful in identifying children with ADHD who may have ASD [N = 435) of the children in this sample have SCQ scores ≥11.Although the continuous analysis of SCQ scores can be viewed as a strength, it is possible that some of the children with particularly high SCQ scores in this sample would have a clinical diagnosis of an ASD, were the diagnosis to be revisited and assessment with the ADI-R  or the Ahave ASD , it is oThere was a wide age range across the sample and as such, it is important to bear in mind that ADHD subtypes are not stable over time and their validity as categorical entities is questionable although symptom domains as dimensions seem to be better validated . Indeed,A further limitation of the study is that although parents were asked to withhold stimulant medication for 24 h prior to cognitive testing, a small proportion of parents (14.4 %) did not follow these instructions. However, this information could not be reliably used as a covariate when examining the association of SCQ score with the cognitive tests due to the high variability of the types and dosages of medication the children took and perhaps more importantly, the variability in time of day the assessments took place (ranging from morning to evening).N = 375). Similarly, the CANTAB IED task was only available for a proportion of the children (N = 252), which may have reduced the power to detect potential effects. The measures of general motor and language development were broad screening questions indicative of developmental problems rather than detailed validated measures, which precluded the assessment of more subtle associations of autistic symptomatology with general development.Although no associations were found between reading and spelling and SCQ scores, the WORD was only assessed in children between 5 and 11 years old  to be able to assess the unique contribution of each of the CD/IQ components to the observed main associations using multivariate regression. Given that we are unable to ascribe a direction of effect to the observed associations in view of the cross-sectional nature of the data, this analytical strategy provides an insight into the origin of effects.Overall, the findings suggest that in children with ADHD, the presence of autistic symptomatology (that is not at a diagnostic level) indexes a more impaired phenotype—encompassing not only severity of ADHD, but also comorbid psychopathology, general cognitive and working memory deficits, and motor and language developmental problems. These findings corroborate and extend previous research –31 and wWith the current proposed changes to DSM-5 and ICD-11, clinical thinking and practice are already moving beyond the restriction of precluding a dual diagnosis of ADHD and ASD. Our results further suggest the merit of this. They highlight that rather than attempting to generate mutually distinctive diagnostic classes, it would be worthwhile for clinicians to acknowledge the strong overlap in young people with ADHD and to consider levels of socio-communicative and RRB traits in those who do not meet diagnostic criteria for ASD, as they index higher levels of comorbidity and cognitive and developmental problems.The presence of undiagnosed deficits in social and communication abilities may also have implications for the effectiveness of behavioural strategies and pharmacological treatment aimed to ameliorate ADHD symptoms. Whilst there is evidence for potential beneficial effects of stimulant medication on ADHD traits in children with ASD , Below is the link to the electronic supplementary material.


This study examined the effect of the incorporation of environmental distractors in computerized continuous performance test (CPT) on the ability of the test in distinguishing ADHD from non-ADHD children. It was hypothesized that children with ADHD would display more distractibility than controls while performing CPT as measured by omission errors in the presence of pure visual, pure auditory, and a combination of visual and auditory distracting stimuli. Participants were 663 children aged 7–12 years, of them 345 diagnosed with ADHD and 318 without ADHD. Results showed that ADHD children demonstrated more omission errors than their healthy peers in all CPT conditions . However, ADHD and non-ADHD children differed in their reaction to distracting stimuli; while all types of distracting stimuli increased the rate of omission errors in ADHD children, only combined visual and auditory distractors increased it in non-ADHD children. Given the low ecological validity of many CPT, these findings suggest that incorporating distractors in CPT improves the ability to distinguish ADHD from non-ADHD children. The diagnosis of Attention Deficit/Hyperactivity Disorder (ADHD) is predominantly based on behavioral symptoms. ADHD is characterized by persistent pattern of inattention and/or hyperactivity-impulsivity, which is maladaptive and inconsistent with a comparable level of developmental age  but the percentage of boys in the ADHD group  was significantly higher than in the control group  . However, when the effect of gender on omission errors was examined using a Linear Repeated Measures model, gender did not have a significant effect .The two groups did not differ in age .First, analyses showed that while gender was not associated with CPT performance, age had a significant effect on it . As can be seen in Table * level interaction revealed that the differences between the two groups varied as a function of the task demands . Within-groups analysis indicated that for the ADHD group, omission errors were significantly higher in all distractors conditions compared to no-distractors. However, in the control group, only combined distractors resulted in an increase in omission errors  non-ADHD children were affected only by the combination of visual and auditory stimuli. This finding confirms the sensitivity of ADHD children to environmental distracting stimuli and is consistent with other studies demonstrating higher distractibility of ADHD children in a variety of cognitive tasks  as distractors , distractors' effect may be confounded with time effects. However, our findings suggest that it might not be the case. In the current study children in the control group did not perform more omission errors at the last level of the test (level 8) than at the first one (level 1). ADHD children performed marginally more omission errors in the last level (level 8), but it is a rather weak/marginal effect which does not seem a cause for concern. Moreover, in both groups, there was no linear increase in omission errors as the test progressed as we would expect if time was negatively associated with sustained attention.The fact that the MOXO-CPT, like most CPT tasks, relied on cognitive stimuli may explain why we failed to identify time effects on performance. Nevertheless, time effect on CPT performance should be further addressed in future studies.The finding that both ADHD and control groups did not perform significantly more omission errors at the end of the test than at the beginning of it  is in contrast to other studies indicating degraded performance in ADHD patients as the task progresses (McGee et al., Several limitation of this study should be considered. First, participation in the study was based on a voluntary agreement of children and their parents. This self-selected sampling strategy tends to be biased toward favoring more cooperative and motivated individuals. Therefore, it is not possible to determine whether this sample also represents other children that were not recruited and whether cooperation is confounded with ADHD variables. This limitation is typical to most clinic-based ADHD studies around the world (Lee and Ousley, In light of the criticism voiced against the low ecological validity of many CPT (Rapport et al., Future research should address the diagnostic utility of the test in larger spectrum of age, in samples with comorbid features, and in different sub-types of ADHD. In addition, future research should investigate the effects of medical treatment on the distractibility of ADHD children.All authors contributed extensively to the work presented in this paper.Itai Berger serves in the scientific advisory board to Neuro-Tech Solutions Ltd. Anat Ben-Simon and Hanoch Cassuto declared no potential conflicts of interest with respect to this article.


OSA patients with ADHD, as compared with those without, had higher anxiety scores and poorer physical component scores of quality of life and higher ESS scores. ADHD scores in patients with OSA were associated with anxiety and depression scores and SF36 physical and mental component scores in bivariate analyses. Thus, in our sample ADHD was not a frequent illness in adult patients with OSA. However, in patients with OSA and ADHD higher levels of anxiety and daytime sleepiness and poorer quality of life was found.AAttention deficit hyperactivity disorder (ADHD) is a common childhood illness. In some patients, this illness may persist into adulthood and an association between ADHD and Obstructive Sleep Apnea (OSA) has been found in childhood. However, it is unclear how OSA and ADHD coincide in adulthood. Therefore, to explore the relationship between OSA and adult ADHD the current investigation utilized a clinically-based cross-sectional survey. Subjects consisted of 81 treatment-naïve OSA patients and 32 controls. Measures included each patient completed a questionnaire regarding sleep, Adult ADHD scale. Clinical information, body mass index, 36-item Short Form Health Survey (SF-36), Epworth Sleepiness Scale (ESS), Hospital Anxiety and Depression Scale, and polysomnography.The subjects with Apnea-Hypopnea Index (AHI) ≥ 5 events/h were defined as patients with OSA. The control group was accepted as individuals with AHI > 0 events/h. The prevalence of adult ADHD was not different between the patients with OSA and the control group [(7.4 % (6/75) vs. 6.3 % (2/30),  Attention deficit hyperactivity disorder (ADHD) is a common childhood illness with prevalence between 3 and 16 %  was calculated by measuring weight and height. All subjects gave written informed consent. The study was approved by the local Ethics Committee. None of the patients or the controls had used nasal CPAP–BPAP due to OSAS.113 subjects admitted to the Sleep Laboratory at the University Department of Medicine, Hospital, for overnight sleep studies, secondary to clinical referral for suspected sleep apnea, were recruited. Exclusion criteria included known diagnosis of diabetes mellitus on medications, acromegaly, chronic renal failure, systemic steroid treatment and hormonal replacement therapy, a history of bipolar disorder, psychosis, anxiety disorder, seizure disorder, substance abuse history or mental retardation. A questionnaire on demographics, sleep symptoms, medical history, and medications was completed. Body mass index (BMI) (kg/m2) with a finger pulse oximeter . Sleep stages were manually scored using standard Rechtschaffen and Kales  > 10 events/h and the control group consisted of subjects with an AHI < 5 events/h.Standard nocturnal polysomnography was performed with recording of sleep stages , measurements of oronasal airflow with nasal canule, snoring, respiratory movements and oxygen saturation , 90.8 % of the healthy controls (specificity)  questionnaire for the assessment of psychological distress. The questionnaire consisted of 14 questions in which the overall severity of anxiety and depression was rated on a four-point scale (0–3). Seven questions were related to anxiety and seven to depression  is a validated 8-item measure of daytime sleepiness. On the ESS respondents estimate how likely they are to doze in eight different situations. The scores are based on a 0-to-24-point scale, with higher scores representing greater levels of sleepiness. The ESS can discriminate the sleepiness level of OSA patients from normal Johns, .The reliability and validity of the Turkish version of the ESS was made by Ağargün et al. .t tests and Pearson correlation analysis. Validity was assessed using Student’s t test. The questionnaire had a high level of internal consistency (Cronbach’s α = 0.80). Paired t tests showed no significant differences between two different occasions. Total and item scores differed significantly between patient and control groups. They concluded that the ESS is a simple and reliable method for measuring persistent daytime sleepiness and may be used in sleep researches in Turkish population.Forty patients with primary hypersomnia and 41 healthy control subjects were included in their study. Internal homogeneity of separate items was assessed using Cronbach’s a statistic and Pearson correlation analysis. Test-retest reliability was assessed with paired The general health related quality of life (HRQL) instrument used in this study was the SF-36 Health Survey (SF-36), Version 1.0 . The SF-36 measures the health domains of physical functioning, role limitations due to physical health problems, body pain, general health, vitality, social function, role limitations due to emotional problems, and mental health. These domains can be further aggregated into two summary scores: physical and mental health summary scores  and the Chi-squared test for categorical parameters (ADHD  % and sex %). Bivariate analyses were performed using Pearson correlation. A p value of <.05 was considered to be statistically significant.All clinical parameters were expressed as mean ± SD, as well as percentages . The patients with OSA and the control group were compared using an unpaired p = 0.8, respectively]. There were eight subjects with ADHD symptoms.Table Table OSA patients with attention deficit/hyperactivity disorder symptoms, as compared with those without, had higher anxiety scores and poorer physical component scores of quality of life and higher Epworth Sleepiness Scale scores Table . AccordiADHD scores in patients with OSA were associated with anxiety and depression scores and SF36 physical and mental component scores in bivariate analyses (Table The current investigation was conducted because it was hypothesized that an association between ADHD symptoms and OSA could be found in adults with OSA. Some studies have suggested an association between OSA and ADHD in children (Cohen-Zion & Ancoli-Israel, However, little is known about this association in adults. Naseem et al.  indicatePolysomnography study of 5- to 7-year-old children by O’Brien et al.  indicateAll of the above studies have been conducted to evaluate the presence of sleep problems in ADHD patients. However, there is no study concerning the frequency of ADHD symptoms and its effects in OSA patients.In our study, we found ADHD symptoms in 7.4 % of OSA patients. OSA patients with ADHD symptoms, as compared with those without, had higher anxiety scores and poorer physical component of quality of life scores and lower apnea-hypopnea index. ADHD scale scores were associated with anxiety and depression scores and physical and mental component quality of life in bivariate analyses. In actuality, depression, anxiety, sleep problems, memory problems, attentional and motivational problems, and quality of life problems are correlated with a significant number of serious psychological disorders and not just ADHD. Yet, studies concerning psychological functioning and quality of life in subjects with ADHD are scarce. In a study by Chao et al. , the 328As with all research this study has limitations that should be noted. Most notably scales have several limitations, and diagnoses should not be made on the bases of these data alone. To diagnose ADHD interviews with patients form the core of the clinical evaluation (Holperin, Newcorn, Schulz, & Sharma, In addition, in OSA, a larger sample size might also have yielded a different finding about the overlap between OSA and ADHD. However, despite these limitations our findings showed that in our sample ADHD did not appear to be frequent in adult patients with OSA. But, the presence of ADHD in OSA did appear linked with poorer quality of life, the more anxiety and the excessive daytime sleepiness, presence of attention deficit/hyperactivity disorder symptom should be kept in mind.


Medication is the most effective treatment of attention-deficit/hyperactivity disorder (ADHD), a common neurobehavioral disorder of childhood. We used data from the 2007-2008 National Survey of Children’s Health to calculate weighted estimates of parent-reported ADHD and medication treatment among US children aged 4 to 17 years, by state and sex-stratified age. State-based rates of ADHD medication treatment ranged from 33% in Nevada to 79% in Mississippi; rates of medicated ADHD were higher among boys than girls at every age. State-based investigations of ADHD medication treatment factors are needed, and our findings may inform these public health efforts. Attention-deficit/hyperactivity disorder (ADHD) is a common neurobehavioral disorder of childhood ; 4.1 milThe National Survey of Children’s Health (NSCH) is a national, random-digit–dialed landline telephone survey of approximately 30 minutes used to characterize the physical, behavioral, and emotional health and health experiences of American children. Conducted twice, the 2007–2008 NSCH had an overall response rate of 46.7%, which incorporates a cooperation rate of 66.0% . NonrespParents and guardians reported whether they had ever been told by a doctor or health care professional that their child (aged 2-17 y) had attention-deficit disorder or ADHD. Respondents also reported whether the child currently had the disorder. If respondents reported a current diagnosis, they were asked whether the child was currently taking medication for ADHD. We used these data to estimate the percentage of children with current ADHD who were taking medication for ADHD and the rate of medicated ADHD among all US children, calculated by dividing the number of children who were currently taking medication for ADHD by the number of those who had valid responses  to the current ADHD diagnosis question. We calculated national, state-based, and sex-by-age rates of these 2 indicators.2 tests and Wald F tests.We restricted the data to 73,122 children aged 4 to 17 years for whom we had valid data on sex and ADHD diagnosis. We incorporated design elements (strata and nonresponse-adjusted weight variables) using SUDAAN version 10.0  to account for the complex survey design and percentages of children taking medication for ADHD treatment by state and sex-stratified age. We compared the prevalence of ADHD medication by sex at each age by using χOf US children aged 4 to 17 years, 4.1 million (7.2%) had a current ADHD diagnosis in 2007, and approximately 2.7 million were taking ADHD medication. The percentage of children with current ADHD and taking ADHD medication was 4.8% , which r2 test, P < .05). Medication treatment rates by age were significantly different as a function of sex ; rates of medication treatment increased during early childhood for both sexes, leveled off among older girls, and decreased among teenaged boys. Medication rates were higher among boys than girls at every age.Among children aged 4 to 17 years, current ADHD was associated with increasing age and male sex ; rates wThe lowest state-based rates of medicated ADHD were documented in 5 Western states ; the highest rates were documented in 5 Southern states . The percentage of children with current ADHD taking ADHD medication was lowest in Nevada, Alaska, and California and highest in Iowa, Missouri, and Mississippi. The national rate of medication treatment among children with current ADHD was 66.3% ; state-based rates ranged from 33% in Nevada to 79% in Mississippi.Nearly 3 million school-aged children were taking medication for ADHD in 2007; this finding is similar to that of a recent analysis of claims data, indicating that 2.8 million (3.5%) US children aged 18 years or younger were taking a stimulant medication in 2008 (The differences in the sex-stratified and state-based rates of medicated ADHD may serve to inform state-based policy and programmatic efforts. Specifically, girls and boys with ADHD may have different medication needs over time; future studies should investigate the potential association between sex differences in medication use and ADHD subtypes. State-based variation in ADHD medication treatment supports reports by the Food and Drug Administration of uneven product distribution of common ADHD medications, contributing to ADHD medication shortages in certain states . Variabi


For math difficulties the association was similar . Our results strengthen the hypothesis that ADHD and learning disorders are comorbid and share, at least partially, the same underlying process. Up to date, it is not clear, on which exact functional processes this comorbidity is based.Attention-deficit/hyperactivity disorder (ADHD) and dyslexia belong to the most common neuro-behavioral childhood disorders with prevalences of around 5% in school-aged children. It is estimated that 20–60% of individuals affected with ADHD also present with learning disorders. We investigated the comorbidity between ADHD symptoms and reading/spelling and math difficulties in two on-going population-based birth cohort studies. Children with ADHD symptoms were at significantly higher risk of also showing reading/spelling difficulties or disorder (Odds Ratio (OR) = 2.80, p = 6.59×10 Attention-deficit/hyperactivity disorder (ADHD) belongs to the most common neuro-behavioural childhood disorders Several environmental factors were suggested to increase the risk for ADHD. Among them, time spent in front of the TV Interestingly, ADHD is associated with other neurological and psychiatric disorders. More than 60% of individuals suffering from ADHD present with one ore more comorbid disorders Two of the most common learning disorders are dyslexia and dyscalculia with prevalence rates of about 5% in school-aged children To date, only few studies have examined the comorbidity between ADHD symptoms and reading/spelling and math difficulties. Especially the relationship between ADHD and dyscalculia has not yet been studied in detail yet.We therefore investigated whether children with ADHD symptoms have a higher risk for also being affected with reading/spelling and math difficulties in a large population-based sample of over 4,000 children aged 10 years, in which also possible confounding factors like maternal smoking had been collected.The LISAplus (The Influence of Life-style factors on the development of the Immune System and Allergies in East and West Germany plus the influence of environment and genetics) and the GINIplus  studies were approved by the local ethics committees  and written consent was obtained from the parents of all study participants.LISAplus and GINIplus are ongoing population-based birth cohort studies.For the LISAplus study, the parents of neonates admitted to maternity hospitals in four German cities  were contacted and 3,097 healthy full-term neonates were recruited in the study between December 1997 and January 1999. Screening, recruitment and exclusion criteria were described elsewhere For the GINIplus study, a total of 5,991 healthy full-term infants born between September 1995 and June 1998 in two regions of Germany  were recruited. The study population is subdivided into an interventional  and an observational group . Children with family history of allergy were assigned to the intervention group and the observational subgroup comprises children with no family history of allergic disease and children whose parents refused to participate in the intervention trial. A description of the study design has been published previously In both studies, reading/spelling disorders or problems were assessed by questionnaire at the 10-year follow-up. ADHD symptoms at the age of 10 years were measured by the German parent-reported version of the Strengths and Difficulties Questionnaire (SDQ) In GINIplus, the presence of a reading/spelling disorder or reading/spelling problems was assessed by one question each. Children, whose parents answered that their child presented with reading/spelling problems as well as with reading/spelling disorder were grouped into the more severe category of reading/spelling disorder, i.e. both categories are disjunct. In LISAplus, parents were asked a single question, i.e. whether their child suffered from reading/spelling disorder or reading/spelling problems.In GINIplus and in LISAplus, parents were also asked via a single question, whether their child suffered from dyscalculia or had problems in mathematics.In order to adjust the multivariable regression models in the analysis for covariates that might lead to confounding of the results, we included gender, age, study (GINIplus or LISAplus) and study center  as basic characteristics of the child. Parental education, single-headed households, maternal age at birth, time which the child spent in front of a screen and pre- and/or postnatal environmental tobacco smoke (ETS) exposure are effect modifiers which have already been reported Current methylphenidate treatment of ADHD symptoms was assessed by questionnaire at the 10-year follow-up.ADHD symptoms were assessed by the hyperactivity/inattention subscale of the SDQ Individuals from both studies, GINIplus and LISAplus, were pooled into one sample. Comorbidity of either reading/spelling difficulties or math difficulties and ADHD symptoms was assessed using logistic regression. Reading/spelling and math difficulties, respectively, were used as dependent and ADHD symptoms as independent variable. Children with normal SDQ hyperactivity/inattention levels were defined as reference category, thus the logistic regression model yielded odds ratios (ORs) and significance values for the comparisons high to normal and borderline to normal SDQ hyperactivity/inattention scores.http://www.r-project.org/).Three different models were applied: no adjustment for covariates , adjustment for the covariates gender, age, study and study centre , additional adjustment for possible modifiers as parental education, age of mother at birth, daily TV/PC use, single parent and ETS exposure . Additionally, we conducted a stratified analysis for gender and study. Statistical significance was defined by a two-sided alpha level of 5%. The results are presented as OR with corresponding 95% confidence interval (CI) and p-value. All analyses were performed using R, version 2.13.1 (−23) for children with borderline and 3.57 (p = 1.48×10−22) for children presenting with a high SDQ-score. After adjusting for gender, age, study, study center, parental education, age of mother at birth, daily TV/PC use, single parent and ETS exposure (adjusted II model), these values dropped to 3.95 (p = 7.27×10−17) and 2.80 (p = 6.59×10−13), respectively. Stratified analyses for GINIplus and LISAplus revealed the same results (data not shown).Sample characteristics for the core phenotypes as well as for covariates are depicted in −12, females: OR = 3.69, p = 3.25×10−06). Unexpectedly, males presenting with high SDQ-score showed a lower risk for also being affected with reading/spelling difficulties than the female group .As gender differences in the prevalence of ADHD −08) as compared to children with high SDQ-score . However, for the risk of showing reading/spelling disorder, results were vice versa: children with high SDQ-score presented with a higher risk for reading/spelling disorder  as compared to children with borderline SDQ-score . In the stratified analysis, boys with borderline SDQ-score were at higher risk for presenting with reading/spelling problems  as compared to boys with high SDQ-score  as compared to males with borderline SDQ-score . For girls, differences between both groups were more striking (−05) as compared to girls with borderline SDQ-score .In GINIplus, reading/spelling problems and reading/spelling disorder were assessed separately. Therefore a sensitivity analysis on the severity of these symptoms for children included in the GINIplus study was performed . Childrestriking : girls w−04) for children with borderline and 2.87 (p = 3.21×10−06) for children presenting with a high SDQ-score. After adjusting for covariates these values were 2.82 (p = 4.90×10−04) and 2.55 (p = 3.63×10−13) respectively. Stratified analyses for GINIplus and LISAplus showed similar results in both studies (data not shown).In addition to comorbidity between ADHD symptoms and reading/spelling difficulties, we also investigated association between ADHD symptoms and math difficulties. 6.8% of children with ADHD symptoms also presented with math difficulties. Children with ADHD symptoms showed a higher risk of also being affected with math difficulties as compared to children without ADHD symptoms . Without−01), males with high SDQ-score had a significantly higher risk . In the female group, children with borderline SDQ-score as well as with high SDQ-score had a significantly higher risk for math difficulties .Concerning comorbidity between ADHD symptoms and math difficulties we observed high gender differences. While males with borderline SDQ-score were not significantly at higher risk for math difficulties as compared to males with normal SDQ-score  out of these individuals. However, including this information as covariate into the analysis did not change the statistical association results for reading/spelling difficulties or for math difficulties (data not shown).We investigated the association between ADHD symptoms and reading/spelling and math difficulties in a pooled sample consisting of children from the LISAplus and GINIplus studies. Children with ADHD symptoms showed a significantly higher risk for reading/spelling difficulties as well as for math difficulties as compared to children presenting with normal SDQ-scores. Observed effects seem to be triggered by gender: while the prevalence for reading/spelling difficulties was higher in males (14.1%) than in females (8.7%), stratification analysis revealed that females showing ADHD symptoms were at a higher risk for also having reading/spelling difficulties than males. Only males with high SDQ-score were at significantly higher risk for having math difficulties while in females both groups- with borderline and high SDQ- showed significantly higher risk. For interpretation of these results, it has to be noted that we do not have information on which symptoms children presented with first – ADHD or dyslexia/dyscalculia symptoms, i.e. we can neither infer causality nor the chronology of symptoms. To diagnose a child with comorbid ADHD ADHD-symptoms need to be present before reading/spelling or arithmetic problems arised Up to date, few studies, partly population-based but with smaller sample sizes than our study, reported comorbidity between ADHD and dyslexia We observed sex-specific differences in the association between ADHD and reading/spelling difficulties. The scale used for assessment of ADHD symptoms in our study combines hyperactivity and inattention symptoms and is not validated for a separate analysis of these two symptoms. When Willcutt et al. We also found high differences in the effect sizes for associations between ADHD and math difficulties in girls and boys. To our knowledge, in the few studies on ADHD and dyscalculia that have already been published, sex-stratified analysis was not performed.Our results are based on a large sample size in which prevalences for the different disorders are similar to already reported estimates. Further strengths are related to the population-based characteristic of both studies and to the consistency of results between GINIplus and LISAplus. In addition, we cautiously adjusted for several socio-economic factors such as parental education and TV/PC use to avoid confounding effects. However, there are also some flaws in the study design. First, ADHD symptoms are assessed by the parent-reported SDQ, a screening instrument. No information on physician diagnosed ADHD was available. Furthermore, presence of dyslexia/dyscalculia symptoms is also based on parental questionnaires and validity of diagnosis may therefore exhibit uncertainness. However, self-reported data on spelling and reading have been reported to show high concordance rates with psychometric tests Only in GINIplus, reading/spelling problems and reading/spelling disorder were assessed separately. The overall results are based on the combined sample exhibiting both – therefore ORs might be overestimated. The same holds true for math difficulties as no distinction between problems in math and dyscalculia was made.Unfortunately, no data on the psychopathology of the parents is available. We can therefore make no conclusions on a possible aggravation of symptoms in families or on a genetic component of the disorders.LISAplus and GINIplus are ongoing longitudinal studies and the 15-year-follow up data will again include questions on reading/spelling and math difficulties. This will enable to analyse the long-term development of the disorders and if special training in reading/spelling lead to a decrease in literacy problems.In our study ADHD symptoms and learning difficulties were comorbid, taking into account possible confounder variables. Several scenarios underlying this comborbidity are thinkable From a diagnostic and therapeutic point of view, it is important to not only check for ADHD or learning disorders alone, but rather for ADHD and reading/spelling or math difficulties in parallel and to adapt the training and therapy accordingly. Children with learning disorders who also present with ADHD symptoms should receive different training as compared to children who present only with dyslexia and dyscalculia because ADHD itself can have an impact on the training methods and training success.We found that children with ADHD symptoms are at higher risk for reading/spelling and math difficulties compared to children without ADHD symptoms. The exact functional process and causality pattern behind this comorbidity remains unknown.


There is often a huge gap between neurobiological facts and firm conclusions stated by the media. Data misrepresentation in the conclusions and summaries of neuroscience articles might contribute to this gap.Using the case of attention deficit hyperactivity disorder (ADHD), we identified three types of misrepresentation. The first relies on prominent inconsistencies between results and claimed conclusions and was observed in two scientific reports dealing with ADHD. Only one out of the 61 media articles echoing both scientific reports adequately described the results and, thus questioned the claimed conclusion. The second type of misrepresentation consists in putting a firm conclusion in the summary while raw data that strongly limit the claim are only given in the results section. To quantify this misrepresentation we analyzed the summaries of all articles asserting that polymorphisms of the gene coding for the D4 dopaminergic receptor are associated with ADHD. Only 25 summaries out of 159 also mentioned that this association confers a small risk. This misrepresentation is also observed in most media articles reporting on ADHD and the D4 gene. The third misrepresentation consists in extrapolating basic and pre-clinical findings to new therapeutic prospects in inappropriate ways. Indeed, analysis of all ADHD-related studies in mice showed that 23% of the conclusions were overstated. The frequency of this overstatement was positively related with the impact factor of the journal.Data misrepresentations are frequent in the scientific literature dealing with ADHD and may contribute to the appearance of misleading conclusions in the media. In synergy with citation distortions and publication biases they influence social representations and bias the scientific evidence in favor of the view that ADHD is primarily caused by biological factors. We discuss the social consequences and the causes of data misrepresentations and suggest a few corrective actions. McKhann ADHD is considered to be the most common neuropsychiatric disorder of childhood with a prevalence rate of approximately 7–9%. Psychostimulants effectively alleviate symptoms in most ADHD children. Hundreds of studies have investigated the neurobiology of ADHD and numerous hypotheses have been proposed. The dopamine deficit theory is still the most popular one Whilst preparing our review on ADHD we noticed several types and cases of data misrepresentation. Therefore, we will mainly defend our view using the example of ADHD. However, there is no reason to think that data misrepresentation occurs only, or is worst, in this particular field. We identified three types of misrepresentation in the scientific literature about ADHD. The first relies on prominent inconsistencies between results and conclusions claimed in the title and summary. The second consists in putting a firm conclusion in the summary while raw data that strongly limit the claim are only given in the results section. In the third, basic and pre-clinical findings are extrapolated to new therapeutic prospects in inappropriate ways. Here, we illustrate each type of misrepresentation by analyzing scientific and media articles reporting on specific topics related to ADHD. Then, we discuss the social consequences and the causes of these misrepresentations. Finally, we suggest a few remedies.In our review of the ADHD literature The Guardian, London, September 21, 2007) adequately described the results and, thus questioned the conclusion claimed by Barbaresi's group  has been cited 30 times in scientific articles. Among them, 20 articles cited the conclusion that dopamine activity is depressed in ADHD without further comment. Apart from our review article This misrepresentation consists of putting in the summary a fixed conclusion while raw data, which strongly limit the relevance of this conclusion, are only given in the result section. To quantify this misrepresentation, we have extensively studied how the scientific literature reports on a specific issue: the association between alleles of the gene coding for the D4 dopamine receptor (DRD4) and ADHD.New York Times says: “Genetic factors may play the most important role in ADHD…. Most of the research on the underlying genetic mechanisms targets the neurotransmitter dopamine. Variations in genes that regulate specific dopamine receptors have been identified in a high proportion of people with ADHD.” Actually, “the most robust finding in ADHD is the association of a variable number tandem repeat polymorphism in exon 3 of the DRD4 gene” To fully appraise this misrepresentation it is illuminating to compare a statement in the media and the corresponding facts. The health guide of the To quantify this misrepresentation in the scientific literature, we examined the summaries of all 219 articles about ADHD that mentioned the DRD4 gene. Articles were classified between review articles (52), animal (or in vitro) studies (24) and research articles in humans (143). This third category was further divided into articles, in which genetic data related to the DRD4 were provided (117) or not (26). In this second category, as well as in animal studies, statements related to the association of the DRD4 gene with ADHD thus corresponded to citations of other articles. In these 219 summaries we counted the presence of specific statements as indicated in Among the 117 primary studies in humans, 74 articles state in their summary that alleles of the DRD4 genes are significantly associated with ADHD but only 19 summaries also mentioned that they confer a small risk. One may argue that summaries are too short to report the details. However, almost the same number of summaries (14) did not mention that it confers small risk but reinforced the view that genetic factors play the most important role in ADHD with an additional statement about its high heritability. Moreover, this misrepresentation always occurs in the summaries of primary articles that cite the association of the DRD4 gene with ADHD but do not report data on it .This misrepresentation is even more robust in review articles. Among the 43 relevant summaries stating that the DRD4 gene is significantly associated with ADHD only 6 mentioned that the 7-repeat allele confers a small risk. Again one may argue that this is due to length constraints, but this explanation is not consistent with other observations. Indeed, 13 summaries did not mention that it confers a small risk but added a statement on the high heritability of ADHD. Likewise, 9 summaries also mentioned the following type of erroneous statement: “The efficacy of stimulant agents confirms that the neurotransmitter abnormalities seen in ADHD are primarily catecholaminergic in origin.” The weakness of this argument has long been underlined On the whole, the case of the association between ADHD and the DRD4 gene shows that the omission of relevant facts limiting the impact of the claim is not restricted to a few scientific articles: it occurs in a vast majority of the summaries. Although in most reports and review articles, the raw data (e.g. odds ratios) were given inside the results section, it is likely that many readers may not check inside the text the relevance of the statement put in the summary (“the DRD4 gene is associated with ADHD”).This misrepresentation is also observed in media articles. Indeed, we looked for press articles reporting on the DRD4 gene and on ADHD. Among 170 relevant articles published from 1996 to 2009, all but 2 stated that polymorphisms of the DRD4 gene are significantly associated with ADHD. Twenty-five articles also mentioned either the raw data or that it confers small risk, while 117 articles did not. Furthermore, 26 articles mentioned the odds ratio (from 1.2 to 1.34) but also put an overstated conclusion (e.g. “These findings strongly implicate the involvement of brain dopamine systems in the pathogenesis of ADHD.”). Thus, the 26 equivocal articles being discarded, 82% of the media articles misrepresented the association between the DRD4 gene and ADHD. This omission rate is very similar to that observed in scientific articles .The literature on the association between the DRD4 gene and ADHD further exemplifies a major publication bias: the most robust effects are reported in initial studies This third type of misrepresentation is illustrated with three examples concerning ADHD . UnjustiUsing the case of ADHD, we investigated 3 types of data misrepresentation in scientific articles: internal inconsistencies, omission of relevant facts and unjustified extrapolation to new therapeutic prospects. The first type was illustrated with only two scientific reports and this selection does not result from a systematic search. Therefore, our observations cannot give a quantitative estimate of the prevalence of this misrepresentation. The second and the third types of misrepresentation were each illustrated with only one specific aspect of the ADHD literature. In both cases we analyzed a corpus of scientific reports selected by a systematic search. Therefore, our study is mainly qualitative and does not provide quantitative information about the extent of data misrepresentation in the ADHD literature as a whole.Our examples of data misrepresentation in scientific reports seem to be correlated with similar misrepresentation in the lay media. Thus, we speculate that data misrepresentation in the scientific literature might play a part in the distortion of data into misleading conclusions in the media. In support of our hypothesis, we observed that many lay articles either cite the conclusions stated in scientific articles or report interviews of the scientific authors.Data misrepresentations in the summaries and conclusions seem to spread in media articles. Indeed, we noticed only a few discrepancies between the conclusions stated in scientific articles and how they are echoed in the media. Overstatements to therapeutic prospects are faithfully reported although some reservations are sometimes expressed. As previously suspected Citation distortion has been already studied in detail regarding a specific neurobiological claim We also observed in the ADHD literature several examples of a major publication bias: the most robust effects are reported in initial studies. This publication bias has already been pointed out in the biomedical literature Although most journal guidelines explicitly condemn them, data misrepresentations, citation distortions and publication biases are frequent in the neuroscience literature. They “provide a distorted view of the reality of scientific data” and reinforce “dominant themes [that] lead to stagnating conformism” There is no doubt that ADHD is a real concern in the sense that most ADHD diagnosed individuals suffer from attention deficit and excessive impulsivity. According to Singh (2008) there are three partially overlapping positions in the public debate about ADHD. The first one posits that ADHD is primarily caused by biological factors, the second that ADHD is caused by a combination of biological and social factors and the third that ADHD is primarily caused by environmental factors Unfortunately, data misrepresentation biases the scientific evidence in favor of the first position stating that ADHD is primarily caused by biological factors. Therefore, this misrepresentation does have social consequences regarding ADHD management: it favors medical interventions over prevention and psycho-social interventions. Moreover, the first position favors research programs that seek to identify biomarkers associated with an ADHD risk. Although no biomarker has yet been already validated in psychiatry, “the current interest in biomarkers is a sign that psychiatry has undergone a methodological shift, away from searching for the causes of a condition towards estimating the probability that the condition is present or will develop” The social consequences also depend on the type of misrepresentation. The first type  and the second (omission of significant facts) do have large consequences when they are echoed in the media. Indeed, they corrupt the message received by the general public, including medical doctors. The third type (exaggerated extrapolations to therapeutic prospects) seems at first glance the least damaging. However, when it occurs in animal studies, it implicitly supports the view that drug treatments are the only solution to mental disorders. Indeed, animal models are not suitable to develop psycho-social interventions. Moreover, and probably far more damaging in the long term to neuroscience, this misrepresentation feeds illusory short-term hopes in patients and their families. For example, animal studies about cellular therapies for spinal cord injury have been put forward by for-profit institutions selling these therapies to unfortunate patients although “these interventions are not yet proven safe and effective by properly conducted clinical trials” Most neuroscientists believe that extrapolating their basic finding to new therapeutic prospects will help their study to be published in a high impact factor journal. Accordingly, our study of the case of ADHD suggests that this type of overstatement is positively associated with publication in prestigious journals. Although it is difficult to know whether this association is causal, there is no neuroscience journal, to our knowledge, stating in their instructions to authors that extrapolation to therapeutic prospects is acceptable only if fully justified. More generally, competition between authors to publish in high rank journals and between journal editors distorts publication of biomedical research in favor of sensationalism Moreover, neuroscience is closely linked to related medical sciences, neurology, psychiatry and neuropharmacology. National research agencies increasingly restrict their support to research projects with potential applications in these 3 medical domains. Therefore, neuroscientists are encouraged to work in line with this institutional demand and to preferentially publish positive results. Even when they are published, negative results or data challenging established dogma are often ignored both by the scientific literature and by the media as exemplified here. Data misrepresentation, citation distortion and publication biases feed the information cascades, which are circularly used to justify the hypotheses put forward in grant proposals First, because our pioneer study is mainly qualitative, we need more studies analyzing the neuroscience discourse. These studies must receive sufficient visibility to draw the attention of the neuroscience community to the extent of data misrepresentation and to its negative consequences. As neuroscience findings are increasingly echoed by the media, we are now, and much more so than in the past, in the public eye. Distortions of neuroscience findings open the door to suspicious public attitudes towards neuroscience and this might result in a decrease of the resources that society will accept being allocated to future research. It is the responsibility of the neuroscience community, and in its long-term interest, to correct this as soon as possible. Second, the key regulators of our publication system are the journal editors. If they collectively reject sensationalism and clearly condemn data misrepresentation, we may expect rapid improvement. This might involve changes in current publication practices as suggested “Internal inconsistencies”. Both articles were found on the occasion of a previous review article about the neurobiology of ADHD. Because this previous work was not a systematic review and because our aim was not to carefully look for all articles exhibiting internal inconsistencies between their results sections and conclusions, both articles represent examples of internal inconsistencies. In other words our study does not provide a reliable quantitative estimate of this particular type of data misrepresentation. In the same section we used the site “ISI Web of Knowledge” to find the 30 scientific articles citing the study by Volkow et al (2007). Because only 8 studies cited the article by Barbaresi et al (2007), we did not analyze them.Our analysis was restricted to scientific articles published in English in journal issues whose publication year was 2009 or earlier. Articles without abstracts were not considered. They were collected from PubMed by means of systematic searches, except for the two articles analyzed in the first section Extrapolating basic and pre-clinical findings to new therapeutic prospects” the impact factor of scientific journals was provided by “ISI Web of Knowledge” using the tool “Journal Citation Reports”. We used the impact factors given by this tool for 2008.In the third section of the results entitled “http://global.factiva.com/sb/default.aspx?NAPC=S&fcpil=fr) and appropriate key words, whose presence was searched in the full texts. Primary scientific articles also given by this database were discarded. When very similar articles were published in distinct newspapers or magazines they were considered as distinct articles. Articles published on web sites did not originate from a systematic search and were found using “Google” and appropriate key words.Articles published in English in newspapers and magazines were systematically searched using the web site “Dow Jones Factiva”  or on that by Barbaresi et al (2007)  were fouWe examined the summaries of scientific articles that mentioned ADHD and the DRD4 gene. Articles were selected via PubMed using the following equation applied to all fields: (attention deficit hyperactivity disorder OR ADHD) AND (D4 OR DRD4). From the 235 retrieved articles we discarded 16 articles whose abstracts did not mentioned DRD4. The remaining 219 summaries were classified as described in Articles published in newspapers and magazines from January 1996 to January 2010 were selected using the following criteria: hyperactivity AND (D4 OR DRD4). Articles, which were not informative enough to know whether the authors have defended the view that the DRD4 gene is associated with ADHD were discarded. The 170 remaining articles were examined and classified according to the same rules as described in “animals”: (attention deficit hyperactivity disorder OR ADHD) AND (mouse OR mice). This search retrieved 178 articles published in 2009 or earlier. We discarded 58 review articles, 16 studies that reported observations not related to the mouse brain and 3 studies not related to ADHD. In the 101 selected articles we examined the conclusions stated in the summary and at the end of the discussion. We rated a study as overstated when the link between ADHD and the studied mice only relied on their behavioral similarities with ADHD symptoms and when the conclusion stated that the findings have provided novel insights into the neurobiology of ADHD. When this overstatement was reinforced by a claim about the clinical relevance of the study, it was rated as of type 2. Studies, which were considered as not overstated, belonged to 3 types: i) mice submitted to experimental conditions mimicking those causally involved in ADHD , ii) investigations into the effects of psychostimulant treatments on the mouse brain and iii) studies on mouse models of ADHD, in which authors refrained from overstating their conclusion. This classification was double-checked independently by two investigators. The classified lists of references are given in All articles related to ADHD and reporting on experiments involving the mouse brain were selected via PubMed with the following search equation applied to all fields using the PubMed limit Using the web site “Dow Jones Factiva” we looked for media articles explicitly reporting on the three scientific studies mentioned in Table S1Distribution of the omission rate with the publication year.(0.04 MB DOC)Click here for additional data file.Text S1Lists of media and scientific articles echoing the studies by Volkow et al (2007) and Barbaresi et al (2007) shown in (0.08 MB DOC)Click here for additional data file.Text S2Scientific and media articles reporting on the association between alleles of the gene coding for the D4 dopamine receptor and ADHD.(0.14 MB DOC)Click here for additional data file.Text S3Scientific studies performed in mice and related to ADHD and media articles that echoed to the 3 scientific articles given in (0.08 MB DOC)Click here for additional data file.


There is evidence for social inequalities in the health status of children with prenatal alcohol exposure (PAE). This study aimed to describe social inequalities in low birth weight (LBW) in children/adolescents with PAE and to examine the contribution of anthropometric and health-related behavioral factors to the explanation of social inequalities. A total of 2,159 participants with parental self-reported moderate to regular PAE  were examined. At similar levels of PAE, the risk of LBW was significantly increased in subjects with a low socioeconomic status (SES) (adjusted odds ratio (OR) 2.78, 95% confidence interval (CI) 1.59, 4.86) and middle SES . Maternal height, maternal body mass index (BMI) and smoking during pregnancy mediated the association. The mediating effect of maternal height was 12.5% to 33.7%. Maternal BMI explained 7.9% of the socioeconomic difference in LBW between the high and low SES groups in children with PAE. The mediating effect of smoking during pregnancy was 17.3% to 31.5%. Maternal height, maternal BMI and smoking during pregnancy together explained 24.4% to 60.1% of the socioeconomic differences in LBW in children with PAE. A large proportion of the socioeconomic differences in LBW in children with PAE can be attributed to anthropometric and health-related behavioral factors.  To examine the question as to why the risk of LBW is greater in offspring with a lower SES at similar levels of PAE, it is necessary to focus on subjects with PAE only, as a multiplicity of risk factors associated with a low SES increase a person’s vulnerability to the adverse effects of PAE by creating a biological milieu within which alcohol develops its major effects ,23,24,25An explanation of the socioeconomic variations in LBW in children with PAE is essential to understand and make recommendations for public health actions to reduce social inequalities in LBW among children with PAE, and to avoid an increase of health inequalities over the life course. Although social inequalities in LBW among alcohol-exposed newborns have been reported, the present study is the first to investigate an explanation for the socioeconomic differences in LBW.The aim of this study was to detect whether social differences exist in the distribution of LBW among children with PAE, and to explain social inequalities in LBW by identifying the contributions of health-related behavior and parental anthropometrics.This study is based on data from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS); this is a nationally representative cross-sectional study including 17,641 children/adolescents (aged 0–17 years) and their parents. The KiGGS study was commissioned by the German Federal Ministry of Health and was designed and conducted by the Robert Koch-Institute. The design of the survey, the process of recruitment and the fieldwork are described in detail elsewhere . BrieflyWritten informed consent according to the Helsinki Declaration was obtained from the participants and their parents or guardians before the individuals entered the study. Approval for the KiGGS study was obtained from the Ethics Committee of the Charité/Universitätsmedizin Berlin (Germany) and the Federal Office for the Protection of Data (20 February 2003).Of the 17,641 participants, 2,331 individuals were exposed to alcohol before birth. PAE was measured through retrospective parental self-reports, questioning whether the mother drank alcohol during pregnancy. Possible answer categories were: “regular”, “moderate” or “no alcohol” intake during pregnancy. The terms “moderate” and “regular” are derived from self-report and may, therefore, be affected by the respondent’s subjective evaluation of such quantities. Participants without information on SES or birth weight, or information provided by non-biological parents and twin and multiple births were excluded from the analysis. This left a study population of 2,159 subjects with PAE for the analysis. Parents were asked to give information on the birth weight of their child. LBW was set to ≤ 2,700 g after calculating the 10th percentile based on information from 16,877 questionnaire responders in the overall cohort study on birth weight . SimilarThe SES was measured with Winkler’s index ,59 whichParental anthropometrics might be associated with the birth weight of the child and the SES. Gestational gain in weight , medium (10–15.9 kg), high (>16 kg)) , maternaInformation on maternal health-related behaviors during pregnancy was restricted to maternal smoking during pregnancy  and was measured by self-report questionnaires.The models were adjusted for maternal age at child’s birth (continuous variable), gender of the child , ethnicity  and parity . Potential mediation was tested by the Baron and Kenny criteria . Each ofIn the first stage, according to Baron and Kenny , the fre(model1) − OR(adjusted model)/(OR(model1) − 1))  and the 95% confidence interval (CI) of LBW for levels of SES (the highest SES was considered the reference) with adjustment for potential confounders  as shown in model 1. Thereafter, model 1 was adjusted for possible explanatory variables separately, to examine the association with LBW (third criterion) and also to examine the contribution of each possible explanatory variable to the explanation of social inequalities in LBW (fourth criterion). All mediators were added to model 1 to identify the total contribution of the mediating variables to the explanation of social inequalities in LBW. The change (decrease or increase) in the OR for parental SES with the higher risk of LBW was calculated with the formula 100 × ((OR1) − 1))  65]. To. To(mode1) − 1)) . The Stap for trend 0.004). Women with a higher SES were older when they gave birth to their child. Of the offspring with a high SES, 87.8% are German compared to 91.3% of the middle SES offspring and 78.5% of the low SES offspring. Parents from the highest social class are taller than parents from the middle and low social class (p < 0.001). The prevalence of low gestational weight gain was highest (19.3%) in the low social class with (p = 0.014). Concerning maternal health-related behavior during pregnancy, mothers from the low social class have the highest moderate and regular smoking rate during pregnancy . p < 0.001). The fathers of children with LBW were shorter than the fathers of children with a higher birth weight (p < 0.016). The prevalence of low gestational weight gain was 40.3% in women who gave birth to a child with LBW compared with a prevalence of 15.6% of low gestational weight gain in women who did not deliver a child with LBW (p < 0.001). In this study, the risk of LBW was increased in the offspring with PAE from the low and middle social class compared with those from the high social class. Maternal height and smoking during pregnancy mediated the relationship between the SES and LBW in children with PAE. Maternal height explained 12.5% to 33.7% of the socioeconomic differences in LBW in children with PAE. Maternal BMI explained 7.9% of the socioeconomic differences in LBW between the low and high SES group in children with PAE. Smoking during pregnancy explained 17.3% to 31.5% of the socioeconomic differences in LBW in children with PAE. Both factors together contributed 24.4% to 60.1% to the explanation of socioeconomic differences in LBW in children with PAE. The study is based on data from a very large and representative national sample. Studies on the reliability of alcohol measurements have demonstrated that drinking during pregnancy is often underreported ,67,68,69The sample in this study could be confounded by various factors. For example, if reports on alcohol intake during pregnancy are related to levels of SES, the social distribution of alcohol-exposed individuals could be biased in unknown ways. Also, if reports on alcohol intake during pregnancy are related to the health status of the child, or to the health status and/or to the health behavior of the mother, or to all of these aspects, the estimates could be biased in unknown ways.In the present study, maternal health-related behavior during pregnancy was restricted to smoking during pregnancy. Additional health-related behaviors (such as caffeine intake during pregnancy and dietary factors) might be relevant in the explanation of why children exposed to similar levels of alcohol before birth from the lower social class are at higher risk for LBW compared with offspring from the upper class. Therefore, additional studies are needed to investigate the role of a wider range of health-related behaviors during pregnancy in the explanation of social inequalities in LBW in children with PAE.Because smoking during pregnancy was self-reported, underreporting might have occurred ,71,72,73The multiple regression model only explained 10.6% of the variance in LBW, even though it was controlled for a large number of confounders. The risk of LBW in the offspring of self-reported moderate to regular drinkers during pregnancy was greater in those with a low and middle SES. This result is in line with others who reported social inequalities in the effects of maternal alcohol intake during pregnancy ,23,24,25The present study has shown that the single effect of smoking during pregnancy explains a substantial amount (17.3% to 31.5%) of the social gradient in LBW in children with PAE. The ingredients of tobacco smoke  cause a decrease in birth weight as these factors are responsible for a reduction in blood flow/oxygen content, and nicotine exposure results in contraction of the placental vessels ,75,76,77The present study shows that the single effect of maternal height explains a considerable amount (12.5% to 33.7%) of the social gradient in LBW in children with PAE. In agreement with others ,79,80,81Maternal BMI explains 7.9% of the socioeconomic difference in LBW between the high and the low SES group in children with PAE; the finding of an increased risk of LBW in women with underweight concurs with other studies ,82 and wMaternal anthropometrics, in terms of maternal height and BMI, as well as maternal health-related behavior, in terms of smoking during pregnancy, contributed to the explanation of social inequalities in LBW among children with PAE. A considerable amount (24.4% to 60.1%) of the socioeconomic differences in LBW in children with PAE was explained by health-related behavioral and anthropometric factors together. Both factors seem to be of importance for the explanation of social inequalities in LBW in children with PAE. This study has shown that LBW in children with PAE is subject to social inequalities. Maternal health-related behavior during pregnancy and maternal anthropometrics make a considerable contribution to our understanding of socioeconomic differences in LBW in children with moderate to regular PAE. LBW acts as a catalyst for diseases throughout the life course. The development of FASD in alcohol-exposed children is related to LBW and this study shows that smoking during pregnancy, lower maternal height, and being underweight trigger the risk of LBW. Both anthropometric and health-related behavioral factors might mediate the association between SES and alcohol-related disorders. To reduce social inequalities in the health of children with PAE at an early stage, it is important to inform women with a lower SES about the adverse effects of tobacco smoke and being underweight on the embryo/fetus. However, prevention campaigns related to the adverse effects of alcohol and tobacco smoke during pregnancy should be designed to reach all women from all social classes.