Determining the minimum clinically important differences for outcomes in the DOMINO trial. Minimal clinically important differences of 3 patient-rated outcomes instruments. Testing minimal clinically important difference: consensus or conundrum? Linking clinical relevance and statistical significance in evaluating intra-individual changes in health-related quality of life. Measurement of health status. Ascertaining the minimal clinically important difference. Clinically useful measures of effect in binary analyses of randomized trials. Smallest detectable and minimal clinically important differences of rehabilitation intervention with their implications for required sample sizes using WOMAC and SF-36 quality of life measurement instruments in patients with osteoarthritis of the lower extremities. The Minimally Clinically Important Difference in Generic Utility-Based Measures The clinical relevance of changes in the Montgomery-Asberg Depression Rating Scale using the minimum clinically important difference approach. Improving the quality of reporting of randomized controlled trials. The CONSORT statement. Validation of a consensus-based minimal clinically important difference (MCID) threshold using an objective functional external anchor. What change in outcomes after cardiac arrest is necessary to change practice? Results of an international survey. Key Methodological Features of Randomized Controlled Trials of Alzheimer’s Disease Therapy What is an acceptable outcome of treatment before it begins? Methodological considerations and implications for patients with chronic low back pain Composing a new song for trials: the Standardized Outcomes in Nephrology (SONG) initiative. CONSORT and QUOROM guidelines for reporting randomized clinical trials and systematic reviews. Establishment of the minimum clinically important difference for the bath ankylosing spondylitis indices: a prospective study.
BACKGROUND Although less likely to be reported in clinical trials than expressions of the statistical significance of differences in outcomes , whether or not a treatment has delivered a specified minimum clinical ly important difference ( MCID ) is also relevant to patients and their caregivers and doctors . Many dementia treatment r and omised controlled trials ( RCTs ) have not reported MCIDs and , where they have been done , observed differences have not reached these . METHODS As part of the development of the Statistical Analysis Plan for the DOMINO trial , investigators met to consider expert opinion- and distribution-based values for the MCID and triangulated these to provide appropriate values for three outcome measures , the  St and ardised Mini-mental State Examination ( sMMSE ) , Bristol Activities of Daily Living Scale ( BADLS ) and Neuropsychiatric Inventory ( NPI ) . Only st and ard deviations ( SD ) were presented to investigators who remained blind to treatment allocation . RESULTS Adoption of values for MCIDs based upon 0.4 of the SD of the change in score from baseline on the sMMSE , BADLS and NPI in the first 127 participants to complete DOMINO yielded MCIDs of 1.4 points for sMMSE , 3.5 for BADLS and 8.0 for NPI . CONCLUSIONS Reference to MCIDs is important for the full interpretation of the results of dementia trials and those conducting such trials should be open about the way in which they have determined and chosen their values for the MCIDs PURPOSE Patient-rated instruments are increasingly used to measure orthopedic outcomes . However , the clinical relevance of modest score changes on such instruments is often unclear . This study was design ed to define the minimal clinical ly important differences ( MCIDs ) of the Disabilities of the Arm , Shoulder , and H and ( DASH ) , QuickDASH ( subset of DASH ) , and Patient-Rated Wrist Evaluation ( PRWE ) question naires for atraumatic conditions of the h and , wrist , and forearm . METHODS We prospect ively analyzed 102 patients undergoing nonoperative treatment for isolated tendinitis , arthritis , or nerve compression syndromes from the forearm to the h and . By phone , patients completed the DASH , QuickDASH , and PRWE at enrollment and at 2 weeks ( n = 78 used in the analysis ) and 4 weeks ( n = 24 used in the analysis ) after initiating treatment . Patients reporting clinical improvement each contributed a single data point categorized as no change ( n = 41 ) , minimal improvement ( n = 30 ) , or marked improvement ( n = 31 ) via a vali date d anchor-based approach . We calculated the MCID as the mean change score for each outcome measure in the minimal improvement group . RESULTS The MCID ( 95 % confidence interval ) for the DASH was 10 ( 5 - 15 ) . The MCID for the QuickDASH was 14 ( 9 - 20 ) . The MCID was 14 ( 8 - 20 ) for the PRWE . The MCID values were significantly different from changes in these outcome measures at times of either no change or marked improvement . The MCID values positively correlated with baseline outcome measure scores to a greater degree than final outcome measure scores . CONCLUSIONS Longitudinal changes on the DASH of 10 points , on the QuickDASH of 14 points , and on the PRWE of 14 points represent minimal clinical ly important changes . We recommend application of these MCID values for group-level analysis when conducting research and interpreting data examining groups of patients as opposed to assessing individual patients . These MCID values may provide a basis for sample size calculations for future investigation using these common patient-rated outcome measures . TYPE OF STUDY /LEVEL OF EVIDENCE Diagnostic III BACKGROUND CONTEXT Various method ologies have been used in attempting to eluci date a st and ard method for calculating minimal clinical ly important difference ( MCID ) . A consensus-based decision ( Initiative on Methods , Measurement , and Pain Assessment in Clinical Trials [ IMMPACT ] group ) suggested a 30 % reduction from baseline as a means to define the MCID of self-report back pain measures . Additionally , important psychometric issues need to be addressed regarding use of an independent measure of the same construct as an external criterion , instead of simply using another self-report measure , when using an anchor-based approach to MCID . PURPOSE The purpose was to test the validity of recently published guidelines regarding MCID using self-report back pain measures and objective socioeconomic outcomes . STUDY DESIGN / SETTING This is a prospect i ve study assessing change scores on commonly used spinal pain assessment measures in patients with chronic disabling occupational spinal disorders ( CDOSDs ) treated in a regional referral rehabilitation center performing interdisciplinary functional restoration . PATIENT SAMPLE The study consisted of consecutive cohort of patients ( N=1,180 ) with CDOSDs completing a functional restoration program . OUTCOMES MEASURES Self-report measures including the Oswestry Disability Index ( ODI ) and the physical component summary ( PCS ) and mental component summary ( MCS ) of the Short Form-36 ( SF-36 ) obtained before and after treatment , were compared with objective socioeconomically relevant outcomes obtained 1 year after treatment ( ie , work status and additional health-care utilization ) , that were the external criteria for evaluating MCID . METHODS Pre- to posttreatment improvement was calculated separately for each measure , and subjects were divided into two groups based on the change in scores relative to baseline : 30 % or greater versus less than 30 % improvement . One-year posttreatment objective socioeconomic outcomes were used as independent external criteria relevant to the CDOSD population . This population is often studied as the most costly and problematic cohort in spine care . RESULTS The ODI and SF-36 MCS were not associated with any of the objective 1-year outcomes used as external criteria . Reduced post-rehabilitation health-care utilization ( based on the percentage of patients pursuing health care from a new provider ) was weakly associated with 30 % or greater improvement on the SF-36 PCS , relative to patients whose scores changed by less than 30 % relative to baseline ( 17.0 % vs. 21.1 % ) . The same was true for the ODI and return-to-work . CONCLUSIONS When objective and independent criteria are used ( socioeconomic outcomes ) in a CDOSD cohort , the 30 % improvement in the ODI and SF-36 may not be a valid MCID index . This replicates similar conclusions made by an independent research group using a distribution-based approach to MCID . The validity of the MCID concept rests on future research using objective external criteria . Moreover , there remains a question whether the term " important " in MCID can be unequivocally and operationally defined as a reliable construct OBJECTIVE To compare the st and ard error of measurement ( SEM ) with established st and ards for clinical ly relevant intra-individual change in an evaluation of health-related quality of life . DESIGN Secondary analysis of data from a r and omized controlled trial . SUBJECTS Six hundred and five out patients with a history of cardiac problems attending the general medicine clinics of a major academic medical center . MEASURES Baseline and follow-up interviews included a modified version of the Chronic Heart Failure Question naire ( CHQ )  and the SF-36 .  The SEM values corresponding to established st and ards for minimal clinical ly important differences ( MCIDs ) on the CHQ were determined . Individual change on the SF-36 was explored using the same SEM criterion . RESULTS One-SEM changes in this population corresponded well to the patient-driven MCID st and ards on all CHQ dimensions ( weighted kappas ( 0.87 ; P < 0.001 ) . The distributions of out patients who improved , remained stable , or declined ( defined by the one-SEM criterion ) were generally consistent between CHQ dimensions and SF-36 subscales . CONCLUSIONS The use of the SEM to evaluate individual patient change should be explored among other health-related quality of life instruments with established st and ards for clinical ly relevant differences . Only then can it be determined whether the one-SEM criterion can be consistently applied as a proxy for clinical ly meaningful change In recent years quality of life instruments have been featured as primary outcomes in many r and omized trials . One of the challenges facing the investigator using such measures is determining the significance of any differences observed , and communicating that significance to clinicians who will be applying the trial results . We have developed an approach to elucidating the significance of changes in score in quality of life instruments by comparing them to global ratings of change . Using this approach we have established a plausible range within which the minimal clinical ly important difference ( MCID ) falls . In three studies in which instruments measuring  dyspnea , fatigue , and emotional function in patients with chronic heart and lung disease were applied the MCID was represented by mean change in score of approximately 0.5 per item , when responses were presented on a seven point Likert scale . Furthermore , we have established ranges for changes in question naire scores that correspond to moderate and large changes in the domains of interest . This information will be useful in interpreting question naire scores , both in individuals and in groups of patients participating in controlled trials , and in the planning of new trials The results of a r and omized clinical trial can be reported using relative and /or absolute estimators of treatment effect . These various measures convey different information , and the choice can influence the physician 's appreciation of the size of treatment effect and , subsequently , treatment decisions . We compare the estimators with respect to the clinical ly relevant information conveyed to physicians , and identify which clinical questions can and can not be answered directly by each . We also identify opportunities for misinterpretation when one estimator is substituted for another , or when an estimator is mislabeled . Clinical ly important questions are addressed most directly by reporting both relative and absolute effects using relative risk and its complement , relative risk reduction , and risk difference and its reciprocal , number needed to treat . This is true of estimates of treatment effect derived from a single trial and also from meta- analysis of a group of trials . Because the control group 's risk affects the numerical value of the odds ratio , the odds ratio can not substitute for the risk ratio in conveying clinical ly important information to physicians . This is especially important when large treatment effects are shown in trials carried out in population s at high baseline risk OBJECTIVE To discuss the concepts of the minimal clinical ly important difference ( MCID ) and the smallest detectable difference ( SDD ) and to examine their relation to required sample sizes for future studies using concrete data of the condition-specific Western Ontario and McMaster Universities Osteoarthritis Index ( WOMAC ) and the generic Medical Outcomes Study 36-Item Short Form ( SF-36 ) in patients with osteoarthritis of the lower extremities undergoing a comprehensive inpatient rehabilitation intervention . METHODS  SDD and MCID  were determined in a prospect i ve study of 122 patients before a comprehensive inpatient rehabilitation intervention  and at the 3-month followup .  MCID was assessed by the transition method . Required SDD and sample sizes were determined by applying normal approximation and taking into account the calculation of power . RESULTS In the WOMAC sections the SDD and MCID ranged from 0.51 to 1.33 points ( scale 0 to 10 ) , and in the SF-36 sections the SDD and MCID ranged from 2.0 to 7.8 points ( scale 0 to 100 ) . Both question naires showed 2 moderately responsive sections that led to required sample sizes of 40 to 325 per treatment arm for a clinical study with unpaired data or total for paired followup data . CONCLUSION In rehabilitation intervention , effects larger than 12 % of baseline score ( 6 % of maximal score ) can be attained and detected as MCID by the transition method in both the WOMAC and the SF-36 . Effects of this size lead to reasonable sample sizes for future studies lying below n = 300 . The same holds true for moderately responsive question naire sections with effect sizes higher than 0.25 . When design ing studies , assumed effects below the MCID may be detectable but are clinical ly meaningless Purpose : To evaluate the use of utility-based generic quality of life measures for establishing the minimally clinical ly important difference ( MCID ) . Background : Utility-based quality of life measures place levels of wellness on a continuum anchored by death ( 0.00 ) and optimum function ( 1.00 ) . Preference measurement studies are used to define the meaning of points along the continuum . Health states that differ by less than 0.03 units can not be discriminated by panels of judges as different from one another . Thus , 0.03 is a reasonable MCID for these measures . Method : Three published studies of patients with Chronic Obstructive Pulmonary Disease ( COPD ) reported data on the Quality of Well-being Scale ( QWB ) before and after pulmonary rehabilitation . One of the studies also r and omly assigned patients to lung volume reduction surgery or to maximal medical therapy . These patients were followed for an average of 29 months . Results : All three evaluations of pulmonary rehabilitation showed changes on the QWB in excess of the proposed 0.03 MCID . QWB changes for patients assigned to lung volume reduction surgery were close to the MCID threshold at one year but grew stronger in subsequent years . Using Norman 's 0.50 st and ard deviation method , all three estimates of rehabilitation effectiveness and the outcomes one year following surgery fall below the MCID . Conclusion : Different methods for estimating MCID lead to different conclusions about the meaning of quality of life changes following pulmonary rehabilitation and lung volume reduction surgery . The preference scaling system in generic utility-based quality of life measures provides a metric that is directly interpretable and avoids many of the criticisms of MCID measures . The method is sensitive enough to suggest clinical ly meaningful benefits of rehabilitation and surgery . Further , quality adjusted life years offer a valuable metric for policy analysis . Utility-based measures of health related quality of life should gain greater use in COPD outcomes research OBJECTIVE To identify the minimal clinical ly important difference ( MCID ) for the Montgomery-Asberg Depression Rating Scale ( MADRS ) in r and omised studies of depression , and to cross-vali date the estimated MCID . DESIGN AND METHODS  Placebo-treated patients from three similarly- design ed , 8-week , double-blind , r and omised depression trials with a stable health status between baseline and Week 1 ( ' no change ' rating on the Clinical Global Impression-Improvement scale ) were eligible . To calculate the MCID using the distribution-based approach , the st and ard deviation was estimated using baseline MADRS data while the reliability parameter was measured as the intraclass correlation coefficient between baseline and Week 1 . For cross-validation , patients from an observational study were matched to identify the ' MCID  change ' ( MADRS change from baseline to endpoint score plus the estimated MCID ) and ' control ' groups . Comparisons of clinical and health-related quality of life measures were performed . RESULTS In total , 177 placebo-treated patients were identified .  MCID estimates for MADRS ranged from 1.6 to 1.9 . A total of 105 matched pairs were identified for the cross-validation analyses . Mean change from baseline in MADRS scores ( 10.6 + /- 8.5 vs. 12.5 + /- 7.9 , p = 0.038 ) and remission rates ( 71.6 % vs. 57.1 % , p < 0.05 ) significantly differed between the ' MCID change ' and ' control ' groups at endpoint . Numerically higher response rates and greater improvements in HRQoL scores in the ' MCID change ' group were also found . CONCLUSION These preliminary findings support the value of the estimated MCID for the MADRS and may aid decision makers in evaluating antidepressant treatment effects and improving long-term patient outcomes THE R AND OMIZED controlled trial ( RCT ) , more than any other methodology , can have a powerful and immediate impact on patient care . Ideally , the report of such an evaluation needs to convey to the reader relevant information concerning the design , conduct , analysis , and generalizability of the trial . This information should provide the reader with the ability to make informed judgments regarding the internal and external validity of the trial . Accurate and complete reporting also benefits editors and review ers in their deliberations regarding su bmi tted manuscripts . For RCTs to ultimately benefit patients , the published report should be of the highest possible st and ard BACKGROUND CONTEXT The minimal clinical ly important difference ( MCID ) is defined as the smallest change in an outcome that a patient would perceive as meaningful . The Initiative on Methods , Measurement and Assessment in Clinical Trials ( IMMPACT ) group proposed defining the MCID as a 30 % improvement in self-reported pain or function . However , this MCID threshold has not been vali date d against an objective physical measure . PURPOSE To test the validity of the IMMPACT-based MCID threshold , using an objective physical measure as an external anchor . STUDY DESIGN / SETTING Prospect i ve study of chronic disabling occupational lumbar disorder ( CDOLD ) patients completing a functional restoration program . PATIENT SAMPLE A consecutive cohort of 743 CDOLD patients . OUTCOME MEASURES Self-report measures of pain-related function were compared with an objective lifting measure , the progressive isoinertial lifting evaluation ( PILE ) , obtained after treatment . METHODS The association between reporting 30 % or greater improvement ( the IMMPACT 's MCID key criterion ) and the PILE score after treatment was assessed . RESULTS A 30 % or greater improvement on the self-report measures was significantly associated with improvement in physical function on the PILE task . CONCLUSIONS Despite extensive use of the MCID to evaluate effects of treatment in spinal disorders , this is the first empirical documentation of the validity of the IMMPACT 's 30 % change criterion compared with an objective physical anchor BACKGROUND Efficient trials of interventions for patients with out-of-hospital cardiac arrest ( OHCA ) should have adequate but not excess power to detect a difference in outcomes . The minimum clinical ly important difference ( MCID ) is the threshold value in outcomes observed in a trial at which providers should choose to adopt a treatment . There has been limited assessment of MCID for outcomes after OHCA . Therefore , we conducted an international survey of individuals interested in cardiac resuscitation to define the MCID for a range of outcomes after OHCA . METHODS A brief survey instrument was developed and modified by consensus . Included were open-ended responses . The survey included an illustrative example of a hypothetical r and omized study with distributions of outcomes based on those in a public use data file from a previous trial . Elicited information included the minimum significant difference required in an outcome to change clinical practice . The population of interest was emergency physicians or other practitioners of acute cardiovascular research . RESULTS Usable responses were obtained from 160 respondents ( 50 % of surveyed ) in 46 countries ( 79 % of surveyed ) .  MCIDs tended to increase as baseline outcomes increased . For a population of patients with 25 % survival to discharge and 20 % favorable neurologic status at discharge , the MCID were median 5 ( interquartile range [ IQR ] 3 , 10 ) percent for survival to discharge ; median 5 ( IQR 2 , 10 ) percent for favorable neurologic status at discharge , median 4 ( IQR 2 , 9 ) days of ICU-free survival and median 4 ( IQR 2 , 8) days of hospital-free survival . CONCLUSION Reported MCIDs for outcomes after OHCA vary according to the outcome considered as well as the baseline rate of achieving it . MCIDs of ICU-free survival or hospital-free survival may be useful to accelerate the rate of evidence -based change in resuscitation care Background : The results of clinical trials are routinely presented in terms of statistical significance , which may or may not indicate clinical significance . Analysis of the minimal clinical ly important difference ( MCID ) of cognitive scales has received little attention to date . Objectives : By review ing the key method ological features ( sample size , duration , statistical and clinical significance ) of clinical trials examining the efficacy of tacrine in the treatment of Alzheimer ’s disease ( AD ) , we assessed their ability to detect clinical ly important changes in cognition . Design : The value for the MCID of the  Mini-Mental State Examination ( MMSE )  was determined by surveying specialists in neurology and geriatric medicine . This value was then used to interpret the clinical significance of the results of published r and omized controlled trials ( RCTs ) assessing the efficacy of tacrine in the treatment of AD and to retrospectively determine their optimal sample size and trial duration . Results : The mean survey MCID for the MMSE was 3.72 ( 95 % confidence interval 3.50–3.95 ) points . Only 2 of 12 tacrine RCTs using the MMSE found a statistically significant difference in MMSE scores for patients taking tacrine  compared with those taking placebo . These improvements were not clinical ly significant when compared with the survey MMSE MCID . For parallel trials of tacrine in AD , the smallest sample size and minimum trial duration required to demonstrate a clinical ly significant difference were calculated to be 53 subjects and 1 year , respectively . Five of the 7 parallel trials met the required sample size ; however , none of them met the criteria for trial duration . Conclusions : When using the MMSE as an outcome measure , no tacrine trial reported results that were clinical ly significant as perceived by clinicians working with dementia patients . Application of a range of plausible MCIDs to the parallel design RCTs also demonstrated that 2 of 7 of these trials did not have sufficient sample size , and none had sufficient duration of treatment to reliably detect clinical ly meaningful changes in cognition . Future clinical trials in this area will need to incorporate the evolving knowledge of MCIDs in order to increase their chance of detecting clinical ly relevant results Underst and ing changes in patient-reported outcomes is indispensable for interpretation of results from clinical studies . As a consequence the term “ minimal clinical ly important difference ” ( MCID ) was coined in the late 1980s to ease classification of patients into improved , not changed or deteriorated . Several method ological categories have been developed determining the MCID , however , all are subject to weaknesses or biases reducing the validity of the reported MCID . The objective of this study was to determine the reproducibility and validity of a novel method for estimating low back pain ( LBP ) patients ’ view of an acceptable change ( MCIDpre ) before treatment begins . One-hundred and forty-seven patients with chronic LBP were recruited from an out-patient hospital back pain unit and followed over an 8-week period . Original and modified versions of the Oswestry disability index ( ODI ) , Bournemouth question naire ( BQ ) and numeric pain rating scale  ( NRSpain ) were filled in at baseline . The modified question naires determined what the patient considered an acceptable post-treatment outcome which allowed us to calculate the MCIDpre . Concurrent comparisons between the MCIDpre , instrument measurement error and a retrospective approach of establishing the minimal clinical ly important difference ( MCIDpost ) were made . The results showed the prospect i ve acceptable outcome method scores to have acceptable reproducibility outside measurement error . MCIDpre was 4.5 larger for the ODI and 1.5 times larger for BQ and NRSpain compared to the MCIDpost . Furthermore , MCIDpre and patients post-treatment acceptable change was almost equal for the NRSpain but not for the ODI and BQ . In conclusion , chronic LBP patients have a reasonably realistic idea of an acceptable change in pain , but probably an overly optimistic view of changes in functional and psychological/affective domains before treatment begins R and omized trials provide the most reliable evidence about the safety and effectiveness of interventions to improve health care and patient outcomes . Unfortunately , the potential for trials to inform treatment decisions remains limited because the outcomes reported often do not resonate with what is directly meaningful and relevant to patients and their clinicians [ 1–3 ] . Further , inconsistent reporting of outcomes across trials prevents assessment of the comparative effect of interventions [ 4 ] . Outcome reporting bias , whereby authors cherry-pick the outcomes they report on the basis of favourable results , may also occur when there is not a st and ardized list of outcomes measured and reported [ 5 , 6 ] . Collectively these problems may undermine the reliability of published trials , leading to inefficient use of scarce research and health care re sources and unintended harm to patients [ 6 ] . Such dissonance in outcomes reported in trials is widespread and evident across all medical specialties . The growing recognition of the problem has prompted large-scale efforts to establish core outcome sets . Core outcome sets are an agreed st and ardized set of outcomes for a specific clinical area that are to be reported as a minimum in all trials in that area [ 7 ] . Outcomes are selected because they are critically important to all stakeholders — namely patients , their clinicians and policymakers— for decision making . Core outcome sets are not design ed to be comprehensive or exclusive . Typically they include only three to five outcomes . Other outcomes that are identified to be important ( i.e. to some stakeholder groups ) may also be recommended for some trials ( Figure 1 ) . The design ated primary outcome of any given trial may be outside the core outcome set and research ers may also opt to add other , trial-specific outcomes , chosen for reasons including responsiveness to the intervention and feasibility . Attempts to st and ardize outcomes began 50 years ago when the World Health Organization published recommendations for the minimum requirements for data collection in cancer trials [ 8 ] . In the 1990s , the Outcome Measures in Rheumatology ( OMERACT ) initiative was formed , and is perhaps the most widely recognized and largest initiative in the field of core outcome development . OMERACT engages patients and health professionals to st and ardize outcome measures for trials in rheumatology [ 9 ] and has pioneered method ologies for developing core outcome sets . The uptake of the OMERACT core outcome sets has improved the consistency of outcomes reported in trials [ 10 ] . In the past decade , core outcome sets in diverse medical specialties , including cardiology , dermatology , surgery , oncology , women ’s health and respiratory disease , have progressively been developed [ 7 , 9–11 ] . The use of core outcome sets is also increasingly being advocated by funders to ensure the relevance and potential impact of research . In the UK , funding organizations , including the National Institute for Health Research and the Health Research Board ( Irel and ) , advise research ers to include core outcome sets if they are available and highlight the  Core Outcome Measures in Effectiveness ( COMET ) data base of core outcomes as a key re source [ 7 ] . The COMET initiative was recently launched to facilitate the development , implementation and evaluation of core outcome sets [ 7 ] . There has been a long-st and ing need in nephrology to develop core outcomes [ 12–14 ] . More than 14 000 r and omized trials are available in the Cochrane Kidney and Transplant Specialised Register [ 15 ] and a search of Clinical Trials.gov trials for ‘ kidney disease ’ yields > 3000 ongoing trials . Despite this considerable investment in trials in nephrology , improvements in outcomes for patients with kidney disease have been modest at best . Across all stages of chronic kidney disease ( CKD ) , patients still have a markedly higher risk of mortality and serious comorbidities , including cardiovascular disease , diabetes , cancer and infection , compared with the general population [ 16–18 ] . Patients with CKD have poor quality of life , particularly if they are on dialysis , to the extent that many patients || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || || As practitioners strive to improve the delivery of patient care , it is increasingly important that they find it easier to identify studies with the highest level of evidence . Once found , there must be some assurance that the studies were carried out satisfactorily and the methodology was sound . To assist in meeting this challenge , the Consoli date d St and ards of Reporting Trials ( CONSORT ) guidelines were developed by a team of dedicated journal editors , epidemiologists , and statisticians . They determined the st and ards for authors reporting the findings of controlled clinical trials . CONSORT comprises a checklist and a flow diagram ( Figs 1 and 2 ) to help improve the quality of reports of r and omized controlled trials ( RCTs ) . It offers a st and ard way for research ers to report their findings . The checklist includes items , based on evidence , that should be addressed in the report ; the flow diagram gives readers a clear picture of the progress of all participants in the trial , from the time they are r and omized until the end of their involvement . The intent is to make the experimental process transparent , flawed or not , so that users of the data can more appropriately evaluate the validity for their purpose s. The key elements start when the research er su bmi ts an article for review and completes the st and ardized forms . The completed checklist should accompany the manuscript through the review process and identify the page on which each item is addressed . The completed flow diagram should appear as a figure in the manuscript . Nearly a year ago , the AJO-DO m and ated a structured abstract with each su bmi ssion ; this is one of the first items on the CONSORT checklist . There are good reasons for this change and for all other requests listed . According to Sharma and Harrison , “ the quality of information provided in journals with structured abstract s is greater than in those with nonstructured abstract s. ” These authors concluded that the quality of information in an abstract improves when a journal changes to a structured format . OBJECTIVE The minimum clinical ly important difference ( MCID ) is the minimum level of change of an outcome measure that is considered to be clinical ly relevant . This prospect i ve study was conducted to establish the minimum level of change in the Bath Ankylosing Spondylitis ( BAS ) indices that is meaningful for both the patient and the clinician . METHODS The BAS question naires [ i.e. , Bath Ankylosing Spondylitis Functional Index ( BASFI ) ; Bath Ankylosing Spondylitis Disease Activity Index ( BASDAI ) ; and Bath Ankylosing Spondylitis patient Global score ( BAS-G ) ] were administered to 125 patients with ankylosing spondylitis ( AS ) at baseline and at the end of a 2-week intensive physiotherapy program . Together with the final assessment , a global vali date d rating scale was used to examine each domain . Receiver operating characteristic ( ROC ) curves were plotted to determine the BAS change score that most accurately classified patients with respect to a clinical ly meaningful change . This analysis was repeated to investigate whether the estimate of change was dependent upon the patients ' baseline scores . RESULTS According to analyses of ROC curves , the MCID are 7 mm or 17.5 % for BASFI : sensitivity = 0.60/specificity = 0.85 ; 10 mm or 22.5 % for BASDAI : sensitivity = 0.65/specificity = 0.82 ; and 15 mm or 27.5 % for BAS-G : sensitivity = 0.61/specificity = 0.74 . MCID values were independent of the patients ' baseline scores ( p = 0.09 to 0.72 ) by regression analysis . CONCLUSION This prospect i ve study gives MCID values for BASFI , BASDAI , and BAS-G that allow translation from the BAS indices to readily understood values for both patients and clinicians
Thus the distribution method can only be used to calculate an absolute MCID as there is no st and ard deviation of baseline score for a relative measure .
The anchor-based method relates the change in
To the Editor : The same patient outcome data from clinical trial results , when presented as absolute or relative changes , may appear different in magnitude .
Recommendations are to report both absolute and relative , or at least baseline , data from which to calculate absolute values [ 1 , 2 ] .
To inform clinical practice , outcome improvements , whether relative or absolute , must be statistically significant and clinical ly meaningful .
A minimal clinical ly important difference ( MCID ) should inform sample size calculations for clinical trials .