Performance of baseline quartile-stratified minimal clinically important difference estimates was superior to individual minimal clinically important difference estimates when compared with a gold standard comparator of important change.

Minimal Clinically Important Difference Estimates Are Biased by Adjusting for Baseline Severity, Not by Regression to the Mean.

Background:The use of minimal clinically important difference (MCID) scores has become increasingly popular amongst clinicians when determining patient response to treatment. Recent evidence has suggested that MCID scores are context specific and a single MCID estimate does not exist within an outcome measure.Objective:The objective of this review was to systematically review the evidence regarding reported MCID scores amongst hip-related patient-reported outcome measures.Methods:Articles were selected following a comprehensive search of PUBMED, CINAHL, EMBASE, and MEDLINE databases (from database inception through October 2012). Inclusion criteria involved: (1) a patient-reported outcome measure used within a hip population was reported, (2) an MCID score was calculated and/or reported, and (3) the article was available in full text.Results:A total of nine studies met the inclusion criteria; seven different patient-reported outcomes were reported amongst varying hip pathologies, a range of follow-up time points, and different treatment approaches. Of the nine studies included, four studies reported MCID estimates on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) ranging from 6·1 to 26·54 on the WOMAC function subscale.Conclusions:This review highlights the wide range of reported MCID scores specific to WOMAC, as well as scores that were calculated from seven other patient-reported outcome measures. We encourage the reader to use caution when utilizing specific MCID estimates as values are highly variable depending upon the study population, follow-up time point, intervention, and methodology from which they were derived.

BackgroundThe Minimal Clinically Important Difference (MCID) assesses what change on a measurement tool can be considered minimal clinically relevant. Although the recall period can influence questionnaire scores, it is unclear if it influences the MCID. This study is the first to examine longitudinally the impact of the recall period of an anchor question and its design on the MCID of COPD health status tools using the COPD Assessment Test (CAT), Clinical COPD Questionnaire (CCQ) and the St. George’s Respiratory Questionnaire (SGRQ).MethodsModerate to very severe COPD patients without respiratory co-morbidities were recruited during 3-week Pulmonary Rehabilitation (PR). CAT, CCQ and SGRQ were completed at baseline, discharge, 3, 6, 9 and 12 months. A 15-point Global Rating of Change scale (GRC) was completed at each follow-up. A five-point GRC was used as second anchor at 12 months. Mean change scores of a subset of patients indicating a minimal improvement on each of the anchor questions were considered the MCID. The MCID estimates over different time periods were compared with one another by evaluating the degree of overlap of Confidence Intervals (CI) adjusted for dependency.ResultsIn total 451 patients were included (57.9 ± 6.6 years, 65% male, 50/39/11% GOLD II/III/IV), of which 309 completed follow-up. Baseline health status scores were 20.2 ± 7.3 (CAT), 2.9 ± 1.2 (CCQ) and 50.7 ± 17.3 (SGRQ). MCID estimates for improvement ranged − 3.1 to − 1.4 for CAT, − 0.6 to − 0.3 for CCQ, and − 10.3 to − 7.6 for SGRQ. Absolute higher – though not significant – MCIDs were observed for CAT and CCQ directly after PR. Significantly absolute lower MCID estimates were observed for CAT (difference − 1.4: CI -2.3 to − 0.5) and CCQ (difference − 0.2: CI -0.3 to −0.1) using a five-point GRC.ConclusionsThe recall period of a 15-point anchor question seemed to have limited impact on the MCID for improvement of CAT, CCQ and SGRQ during PR; although a 3-week MCID estimate directly after PR might lead to absolute higher values. However, the design of the anchor question was likely to influence the MCID of CAT and CCQ.Trial registrationRIMTCORE trial #DRKS00004609 and #12107 (Ethik-Kommission der Bayerischen Landesärztekammer).

Estimating minimal clinically important difference (MCID) for gastrointestinal symptoms in cystic fibrosis

Patient-reported outcome measures (PROMs) are essential instruments for assessing postsurgical pain-related outcomes from the patient's perspective. The concept of minimal clinically important difference (MCID) aims to identify the smallest change in PROMs that is meaningful to patients. In this multicenter study, data were used to calculate MCIDs for several PROMs assessing pain intensity and physical function after surgery and to perform a sensitivity analysis. Data from 2,661 patients undergoing sternotomy, total knee arthroplasty, breast surgery, or surgery related to endometriosis, recruited from 18 centers in 10 European countries, were included in the analysis. Eight PROMs were collected on days 1 and 3 after surgery, assessing pain intensity (at rest, average, worst, during movement, during physiotherapy) and physical function (in bed, during movement, during physiotherapy). MCIDs were calculated using a combination of distribution-based (30% of SD, standard error of the measurement) and anchor-based (calculating the absolute change between day 1 and day 3 for patients reporting "minimal improvement" or "minimal worsening" on 7-point global and specific impression of change scales) methods. The MCID estimates for pain intensity ranged from 1.2 (at rest) to 1.6 (during activity), while physical function was consistent between 1.5 (in bed) and 1.6 (during physiotherapy) on an 11-point scale. Sensitivity analyses revealed no significant difference in MCID estimates between symptom improvement and worsening for all PROMs. However, baseline pain influenced MCID estimates, with higher baseline pain leading to patients reporting higher changes as meaningful ( e.g. , for pain at rest, MCID mild pain 1.0, MCID severe pain 2.1). The authors found differences between MCID estimates for eight PROMs related to pain intensity and physical function. Baseline values appear to have a significant impact on what patients consider to be a minimal relevant change, which should be addressed in future studies.

Establishing the Minimal Clinically Important Difference and Substantial Clinical Benefit for the Pain Visual Analog Scale in a Postoperative Hand Surgery Population

The Wisconsin gait scale – The minimal clinically important difference

The smallest worthwhile effect is superior to the MCID for estimating acceptable benefits of knee arthroplasty

BackgroundUsing a real dataset, we highlighted several major methodological issues raised by the estimation of the Minimal Clinically Important Difference (MCID) of a Patient-Reported Outcomes instrument. We especially considered the management of missing data and the use of more than two times of measurement. While inappropriate missing data management and inappropriate use of multiple time points can lead to loss of precision and/or bias in MCID estimation, these issues are almost never dealt with and require cautious considerations in the context of MCID estimation.MethodsWe used the LIGALONGO study (French Randomized Controlled Trial). We estimated MCID on the SF-36 General Health score by comparing many methods (distribution or anchor-based). Different techniques for imputation of missing data were performed (simple and multiple imputations). We also consider all measurement occasions by longitudinal modeling, and the dependence of the score difference on baseline.ResultsThree hundred ninety-three patients were studied. With distribution-based methods, a great variability in MCID was observed (from 3 to 26 points for improvement). Only 0.2 SD and 1/3 SD distribution methods gave MCID values consistent with anchor-based methods (from 4 to 7 points for improvement). The choice of missing data imputation technique clearly had an impact on MCID estimates. Simple imputation by mean score seemed to lead to out-of-range estimate, but as missing not at random mechanism can be hypothesized, even multiple imputations techniques can have led to an slight underestimation of MCID. Using 3 measurement occasions for improvement led to an increase in precision but lowered estimates.ConclusionThis practical example illustrates the substantial impact of some methodological issues that are usually never dealt with for MCID estimation. Simulation studies are needed to investigate those issues.Trial registrationNCT01240772 (ClinicalTrials.gov) registered on November 15, 2010.

Utility score is a preference-based measure of general health state – where 0 is equal to death, and 1 is equal to perfect health. To understand a patient's smallest perceptible change in utility score, the minimal clinically important difference (MCID) can be calculated. However, there are multiple methods to calculate MCID with no consensus about which method is most appropriate. The aim of this study is to calculate MCID values for the Veterans-RAND 12 (VR12) utility score using varying methods. Our hypothesis is that different methods will yield different MCID values.A tertiary institutional registry (SMART) was used as the study cohort. Patients who underwent unilateral TKA for osteoarthritis from January 2012 to January 2020 were included. Utility score was calculated from VR12 responses using the standardised Brazier's method. Distribution and anchor methods were used for the MCID calculation. For distribution methods, 0.5 standard deviations of the baseline and change scores were used. For anchor methods, the physical and emotional anchor questions in the VR12 survey were used to benchmark utility score outcomes. Anchor methods included mean difference in change score, mean difference in 12 month score, and receiver operating characteristics (ROC) analysis with the Youden index.Complete case analysis of 1735 out of 1809 eligible patients was performed. Significant variation in the MCID estimates for VR12 utility score were reported dependent on the calculation method used. The MCID estimate from 0.5 standard deviations of the change score was 0.083. The MCID estimate from the ROC analysis method using physical or emotional anchor question improvement was 0.115 (CI95 0.08-0.14; AUC 0.656).Different MCID calculation methods yielded different MCID values. Our results suggest that MCID is not an umbrella concept but rather many distinct concepts. A general consensus is required to standardise how MCID is defined, calculated, and applied in clinical practice.

Background. The interpretation of the change scores of the Barthel Index (BI) in follow-up or outcome studies has been hampered by the fact that its minimal clinically important difference (MCID) has not been determined. Objective. This article was written to establish the MCID of the BI in stroke patients. Methods. Both anchor-based and distribution-based methods were used to establish the MCID. In the anchor-based method, 43 stroke inpatients participated in a follow-up study designed to determine the MCID of the BI using patients' global ratings of the activities of daily living function on a 15-point Likert-type scale. The mean change scores on the 20-point scale of the BI of the MCID group, based on the patients' ratings on the Likert-type scale, served as the first estimate of the MCID. In the distribution-based method, 56 chronic stroke patients participated in the test-retest reliability study to determine the MCID of the BI. One standard error of measurement (SEM) served as the second estimate for the MCID. The larger MCID value of the 2 estimates was chosen as the MCID of the BI. Results. In the anchor-based study, there were 20 patients in the MCID group, with a mean change score of 1.85 points (ie, the first MCID estimate). In the distribution-based study, the SEM based on test-retest agreement was 1.45 points (ie, the second MCID estimate). The MCID of the BI in stroke patients was estimated to be 1.85 points. Conclusion. The authors' results, within the limitations of their design, suggest that if the mean BI change score within a stroke group has reached 1.85 points in a study, the change score on the BI can be perceived by patients as important and beyond measurement error (ie, such a change score is clinically important).

A systematic review of estimates of the minimal clinically important difference and patient acceptable symptom state of the Western Ontario and McMaster Universities Osteoarthritis Index in patients who underwent total hip and total knee replacement

Concordance between important change and acceptable symptom state following knee arthroplasty: the role of baseline scores

Crohn's disease (CD) is a chronic inflammatory illness characterized by episodic abdominal pain, diarrhoea, fever, bleeding and obstruction. While the Crohn's Disease Activity Index (CDAI) remains the most commonly accepted measure for assessing the disease status in clinical trials, patient-reported outcome (PRO) instruments are being utilized more frequently to provide information about health-related quality of life (HRQOL). To facilitate interpretation of results, it is common to identify a meaningful unit of PRO score change, such as a minimal clinically important difference (MCID). To define and apply MCID estimates for the SF-36 and EuroQol-5D visual analogue scale (EQ-5D VAS) for use in CD treatment evaluation. Data from two phase III randomized controlled trials of certolizumab pegol were utilized. MCID estimates were computed from one trial using anchor-based and distribution-based methods. These estimates were applied to data from the other trial. SF-36 PCS and MCS MCID estimates ranged from 1.6 to 7.0 and 2.3 to 8.7 respectively, depending on approach. EQ-5D VAS MCID estimates ranged from 4.2 to 14.8. For the first time, the MCID values provided interpretation guidelines for PRO results in CD. This research demonstrates that patients treated with certolizumab pegol benefit from meaningful and sustained HRQOL improvements.

A systematic review of estimates of the minimally clinically important difference and patient acceptable symptom state of the western ontario and mcmaster universities osteoarthritis index in patients who underwent total hip and total knee replacement