Further psychometric evaluation of the WOUND-Q: A responsiveness study.

The WOUND-Q is a modular patient-reported outcome measure (PROM) with 13 scales measuring constructs across 4 domains (i.e., wound characteristics, health related quality of life, experience of care and wound treatment). The psychometrics of the WOUND-Q were previously assessed and the 13 scales evidenced good validity and reliability. However, the responsiveness (i.e., ability to detect clinical change) of the WOUND-Q has yet to be assessed. The objective of this study was to evaluate responsiveness for 9 WOUND-Q scales that assess outcomes, in a sample of people 18 years of age or older with chronic wounds that were present for at least 3 months. This study conducted a 4 month follow-up of 421 participants who completed the WOUND-Q as part of a previous psychometric study. Participants completed an online survey answering questions about their current wound state (e.g., number, type, size, smell, drainage), anchor questions about change, as well as the WOUND-Q scales that they had completed in their initial assessment. Pre-defined hypotheses were tested with a 75% acceptance threshold indicating sufficient evidence of responsiveness. Minimally important differences (MIDs) were also calculated using both anchor-based and distribution-based methods. Of 390 invited participants, 320 provided responses, ranging in age from 19 to 84 years. Acceptance of hypotheses ranged from 60% to 100%, with only the Symptom scale not meeting the 75% threshold. The findings of this study provide evidence that the WOUND-Q can validly measure clinical change in patients with chronic wounds.

A scoping review of the use of minimally important difference of EQ-5D utility index and EQ-VAS scores in health technology assessment.

OBJECTIVES: Estimates of minimally important differences (MID) can assist interpretation of data collected using patient-reported outcomes (PRO), but variability exists in the emphasis placed on MIDs in health technology assessment (HTA) guidelines. This study aimed to identify to what extent information on the MID of a commonly used PRO, the EQ-5D, is required and utilised by selected HTA agencies. METHODS: Technology appraisal (TA) documents from HTA agencies in England, France, Germany, and the US between 2019 and 2021 were reviewed to identify documents which discussed MID of EQ-5D data as a clinical outcome assessment (COA) endpoint. RESULTS: Of 151 TAs utilising EQ-5D as a COA endpoint, 58 (38%) discussed MID of EQ-5D data. Discussion of MID was most frequent in Germany, in 75% (n = 12/16) of Gemeinsamer Bundesausschuss (G-BA) and 44% (n = 34/78) of Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen, (IQWiG) TAs. MID was predominantly applied to the EQ-VAS (n = 50), most frequently using a threshold of > 7 or > 10 points (n = 13). G-BA and IQWiG frequently criticised MID analyses, particularly the sources of MID thresholds for the EQ-VAS, as they were perceived as being unsuitable for assessing the validity of MID. CONCLUSION: MID of the EQ-5D was not frequently discussed outside of Germany, and this did not appear to negatively impact decision-making of these HTA agencies. While MID thresholds were often applied to EQ-VAS data in German TAs, analyses were frequently rejected in benefit assessments due to concerns with their validity. Companies should pre-specify analyses of continuous data in statistical analysis plans to be considered for treatment benefit assessment in Germany.

Health-related quality of life in pregnant women with type 1 diabetes and associations with maternal and neonatal complications.

PURPOSE: Preexisting type 1 diabetes is a stressful situation for women in pregnancy. We aimed to evaluate health-related quality of life (HRQoL) during pregnancy in women with type 1 diabetes and examine the association between HRQoL and pregnancy outcomes. METHODS: This multicenter prospective cohort study involved 115 pregnant women with type 1 diabetes from 11 participating centers in China. HRQoL was investigated in three trimesters using European Quality-of-life 5-Dimension 5-Level questionnaire (EQ-5D-5 L). Chinese time trade-off value method was used to calculate the EQ-5D-5 L score. Multivariable logistic regression model was used to evaluate the effect of HRQoL on maternal and neonatal outcomes. Receiver operating characteristic curves and distribution-based methods were employed to estimate minimally important differences of clinically important decline in HRQoL. RESULTS: 50.43% of the studied women with type 1 diabetes reported impaired HRQoL in pregnancy. Estimated maternal HRQoL significantly decreased from early to mid-pregnancy (mean EQ-5D-5 L score 0.97 in the first trimester and 0.91 in the second trimester) and improved slightly in late pregnancy (mean EQ-5D-5 L score 0.95). Multivariable regression model showed that women who experienced impaired HRQoL in pregnancy had higher risk of hypertensive disorder, preterm birth, and composite pregnancy outcome. The estimated minimally important difference for composite pregnancy outcome was -0.045 to -0.043. CONCLUSIONS: Experiencing impaired HRQoL during pregnancy was associated with a higher risk of hypertensive disorder and preterm birth in women with type 1 diabetes. The estimated minimally important difference of EQ-5D-5 L might serve as a clinically important tool in prenatal care. TRIAL REGISTRATION: No.ChiCTR1900025955.

Common methods of determining meaningful change in clinical practice: implications for precision patient-reported outcomes.

PURPOSE: Patient-reported outcomes (PROs) are used in clinical practice for several purposes, including to monitor whether a treatment is working or whether a patient is experiencing adverse events from treatment. This study surveyed oncology providers (OP) and mental health providers (MHP) to determine how clinicians from different disciplines determine individual-level meaningful change on PROs. Understanding how clinicians determine change on PROs could help inform methods for individualizing meaningful change definitions, an approach we have dubbed "Precision PROs". METHODS: Three hundred and forty-seven providers utilizing PROs completed an online survey about PRO use to monitor patients in clinical practice. A question on methods used to determine individual-level meaningful change on PROs was developed with input from clinicians. Multivariate logistic regression analyses were used to assess whether specific methods were associated with clinician characteristics. RESULTS: The most commonly reported method was comparing the previous score to the current score (65%). Other methods included examining the numerical scores without a visual aid (59%), considering other factors affecting scores (42%), comparing scores to norms (31%) and using a graph of scores (29%). Provider age was negatively associated with odds of using a graph (OR = 0.95, 95% CI 0.91, 1.0) but no other method. Provider gender, hours per week in clinical practice and years in practice were not associated with odds of using a specific method. CONCLUSIONS: Most providers determined individual-level meaningful change without a visual aid and used only the previous score and current score, the minimum number (2 scores) to determine change. Consistent with current practice, future research on methods of determining within-individual meaningful change for clinical use should focus on methods requiring two rather than three or more scores. When attempting to personalize within-individual change definitions (Precision PROs), methods examining a baseline and single follow-up may be most useful for clinical practice.

The effects of greater frequency of two most prevalent bothersome acute respiratory symptoms on health-related quality of life in the 2020 US general population.

PURPOSE: Upper respiratory tract infections (URTI) and related symptoms are widespread and a common reason for visiting primary care with cough and sore throat being most prevalent. Despite their impact on daily activities, no studies have explored the impact on health-related quality of life (HRQOL) in representative general populations. We aimed to understand the short-term impact of the two most prevalent URTI symptoms on HRQOL. METHODS: Online 2020 surveys including acute (≤ 4 weeks) respiratory symptoms (sore throat and cough) and SF-36® health survey (all with 4-week recall) were analysed using analysis of covariance (ANCOVA) in comparison with adult US population norms. Linear T-score transformation of SF-6D utility (ranging from 0 to 1) enabled direct comparisons with SF-36. RESULTS: In total, 7563 US adults responded (average age: 52 years; range: 18-100 years). Sore throat and cough lasting at least several days were experienced by 14% and 22% participants, respectively. Chronic respiratory conditions were reported by 22% of the sample. A clear and consistent pattern of group HRQOL means declining significantly (p < 0.001) for acute cough and sore throat symptom presence and severity. Declines were observed on SF-36 physical (PCS) and mental component (MCS) and health utility (SF-6D) scores controlling for covariates. Those reporting respiratory symptoms 'most days' declined ≥ 0.5 standard deviation (minimal important difference [MID]) worse with averages at the 19th and 34th centiles for cough on the PCS and MCS, and 21st to 26th centile for sore throat. CONCLUSION: Declines in HRQOL with acute cough and sore throat symptoms consistently exceeded MID standards and should not be ignored as self-limiting without intervention. Future studies on early self-care for symptom relief and its implications on HRQOL and health economics would be valuable to understand the benefits on healthcare burden and need for updating treatment guidelines.

Vascular Quality of Life Questionnaire-6 Before and After Supervised Exercise Therapy in Patients with Intermittent Claudication.

OBJECTIVE: The Vascular Quality of Life Questionnaire-6 (VascuQoL-6) is a short, disease specific instrument used to determine health related quality of life (HRQoL) in patients with peripheral arterial disease. This study aimed to assess the minimally important difference (MID) and substantial clinical benefit (SCB) of the VascuQoL-6 in Dutch patients with intermittent claudication (IC) receiving supervised exercise therapy (SET). METHODS: Consecutive patients with IC who were recruited from a single centre between January 2016 and December 2016 completed the VascuQoL-6 before initiation and after three months of SET. They subsequently answered an anchor question rating their current health status as much improved, improved, unchanged, deteriorated, or much deteriorated, compared with baseline. The MID for improvement and deterioration and SCB were calculated using anchor based and distribution based methods. RESULTS: A total of 124 patients with IC (58% male, mean age 68 years) completed the study protocol. Baseline VascuQoL-6 scores increased from 16.3 ± 4.4 to 18.7 ± 3.8 after three months of SET (p < .001). MID values ranged from +2.0 to +3.8 points regarding HRQoL improvement and from +0.2 to -2.2 points regarding HRQoL deterioration. The SCB ranged from +3.7 to +5.0 points. Depending on the MID approach, 32% - 41% of patients achieved a clinically meaningful improvement in HRQoL. CONCLUSION: Approximately one in three patients with IC reported a clinically meaningful improvement in HRQoL after three months of SET. The range of MID and SCB values provides caregivers with an idea of how much change in VascuQoL-6 scores is considered relevant or substantial by their patients. Applying cutoff points for MID and SCB may optimise the interpretation of trial results and may help to set a benchmark for success of SET.

Validation and minimally important difference of the Child-OIDP in a socioeconomically diverse sample of Indian adolescents.

INTRODUCTION: While different measures have been validated and used to assess the oral health related quality of life (OHRQoL) of children and adolescents, no previous study has tested the psychometric performance of OHRQoL amongst the most marginalized adolescents, living in extremely deprived neighbourhoods like urban slums and resettlement areas in modern cities. Our study assessed the internal consistency reliability, construct validity and Minimally Important Difference (MID) of the Child-OIDP in a sample of adolescents aged 12-15 years reporting oral health problems that lived in three different types (including two extremely vulnerable) of neighbourhoods (urban slums, resettlement colonies, and middle and upper middle-class neighbourhoods) in the National Capital Territory of Delhi. METHODS: We conducted data analysis on a cross-sectional study, comprising of 840 adolescents. The Child-OIDP was used as a measure of OHRQoL. Internal consistency reliability was tested using the standardized Cronbach's Alpha Coefficient. The Child-OIDP was also tested for content and construct validity (the latter through the median test), while a distribution-based approach was used to identify the MID. RESULTS: The Indian Child-OIDP showed good internal consistency, as the Cronbach's alpha coefficient was 0.77. Inter-item correlation coefficients among the items ranged from 0.13 to 0.50, with the mean inter-item correlation being 0.30. The corrected item-total correlations ranged from 0.30 (social contact) to 0.54 (speaking). For construct validity, the Child-OIDP extent was significantly associated with three subjective oral and general health variables in the expected direction. The calculated effect sizes for these differences indicated that they were moderate (0.50-0.79). We also calculated the standard error of measurement (SEM) of Child-OIDP extent as 0.75. CONCLUSION: This study demonstrated that the Indian Child-OIDP is a reliable and valid measure for the assessment of the oral health related quality of life among Indian adolescents especially from marginalised and socioeconomically vulnerable groups. This is an essential step towards assessing oral health and evaluating oral health promotion interventions in those populations and settings.

Frailty change based on minimally important difference in nursing home residents: FIRST cohort study findings.

BACKGROUND: Frailty is common among residential aged care services (RACS) residents; however, little is known about how frailty changes over time in this population. This study aimed to estimate minimally important difference (MID) in frailty to then describe: frailty change over 12 months; and factors associated with worsening frailty. METHODS: Prospective cohort study across 12 RACS sites of a single aged care organisation in South Australia (n = 548 residents, mean age 87.7 ± 7.2 years, 72.6% female). Frailty was measured using a frailty index (FI) with 12 months between baseline and follow-up. MID was calculated cross-sectionally (anchor-based using self-reported health, and ½SD for distribution-based). RESULTS: Between-person MID for the FI was identified as 0.037 (anchor-based) and 0.063 (distribution-based). Using the conservative value of 0.063 as the basis for change, 32.3% (n = 177) of residents remained stable, 13.7% (n = 75) improved, 33.0% (n = 181) worsened and 21.0% (n = 115) died over 12 months. In a multivariable analysis, significant predictors of the dichotomous outcome of worsening and death at 12 months were: being malnourished (odds ratio (OR) = 2.15, 95% confidence interval (CI) = 1.23, 3.75), at risk of malnutrition (OR = 1.98, 95%CI = 1.34, 2.91) and diabetes (OR = 1.61, 95%CI = 1.06, 2.42) compared to those who remained stable or improved. CONCLUSIONS: A 6.3% change in frailty for RACS residents is a conservative MID. Frailty is dynamic in RACS residents, and stability or improvement was possible even for the most-frail. Treatments such as nutritional interventions, exercise and diabetes management are likely to benefit frailty.

Frailty state utility and minimally important difference: findings from the North West Adelaide Health Study.

BACKGROUND: frailty is a dynamic condition for which a range of interventions are available. Health state utilities are values that represent the strength of an individual's preference for specific health states, and are used in economic evaluation. This is a topic yet to be examined in detail for frailty. Likewise, little has been reported on minimally important difference (MID), the extent of change in frailty status that individuals consider to be important. OBJECTIVES: to examine the relationship between frailty status, for both the frailty phenotype (FP) and frailty index (FI), and utility (preference-based health state), and to determine a MID for both frailty measures. DESIGN AND SETTING: population-based cohort of community-dwelling Australians. PARTICIPANT: in total, 874 adults aged ≥65 years (54% female), mean age 74.4 (6.2) years. MEASUREMENTS: frailty was measured using the FP and FI. Utilities were calculated using the short-form 6D health survey, with Australian and UK weighting applied. MID was calculated cross-sectionally. RESULTS: for both the FP and FI, frailty was significantly statistically associated (P < 0.001) with lower utility in an adjusted analysis using both Australian and UK weighting. Between-person MID for the FP was identified as 0.59 [standard deviation (SD) 0.31] (anchor-based) and 0.59 (distribution-based), whereas for the FI, MID was 0.11 (SD 0.05) (anchor-based) and 0.07 (distribution-based). CONCLUSIONS: frailty is significantly associated with lower preference-based health state utility. Frailty MID can be used to inform design of clinical trials and economic evaluations, as well as providing useful clinical information on frailty differences that patients consider important.

The minimally important difference of the Gastrointestinal Quality of Life Index for symptomatic gallstone surgery.

INTRODUCTION: The Gastrointestinal Quality of Life Index (GQLI) is used to measure domains of health and symptoms among people with gastrointestinal disorders. The objective of this study is to calculate the smallest change in the GQLI that is perceived by patients as meaningful among a sample of English-speaking adult patients undergoing elective laparoscopic cholecystectomy for treatment of symptomatic gallbladder disease. MATERIALS AND METHODS: The study is based on retrospective analyses of a sample of participants completing the GQLI and the EQ-5D(3L) preoperatively and six months postoperatively in Vancouver, Canada. Patients are excluded if they are less than 19 years of age, cannot communicate in English, or reside in a long-term care facility. The MID is calculated for the GQLI's domains using distribution and anchor-based methods. RESULTS: Among eligible patients, the participation rate was 51%. The estimated MID for the overall GQLI value ranged between 4.32 and 11.44. There were no statistically significant differences in the GQLI's MID values between sexes or age subgroups. There were statistically significant differences in the GQLI's MID values by baseline health status. DISCUSSION: This study should provide some comfort that the MID values used in discussing change in health and symptoms with elective cholecystectomy patients are robust to sex. Although the sample size may have been inadequate for age-based analyses, the study found large differences in MID values between age subgroups. Statistically significant differences in MID values based on preoperative health supports reporting MID values separately by baseline value. Further research should explore whether age-based differences in MID values exist using larger samples.

Between-group minimally important change versus individual treatment responders.

PURPOSE: Estimates of the minimally important change (MIC) can be used to evaluate whether group-level differences are large enough to be important. But responders to treatment have been based upon group-level MIC thresholds, resulting in inaccurate classification of change over time. This article reviews options and provides suggestions about individual-level statistics to assess whether individuals have improved, stayed the same, or declined. METHODS: Review of MIC estimation and an example of misapplication of MIC group-level estimates to assess individual change. Secondary data analysis to show how perceptions about meaningful change can be used along with significance of individual change. RESULTS: MIC thresholds yield over-optimistic conclusions about responders to treatment because they classify those who have not changed as responders. CONCLUSIONS: Future studies need to evaluate the significance of individual change using appropriate individual-level statistics such as the reliable change index or the equivalent coefficient of repeatability. Supplementing individual statistical significance with retrospective assessments of change is desirable.

Children's Acute Cough-Specific Quality of Life: Revalidation and Development of a Short Form.

PURPOSE: Acute cough in children has a significant impact on the child and family. Relevant quality of life (QoL) instruments are essential for high-quality clinical research. This study aimed to (1) revalidate the 16-item Parent-proxy Children's Acute Cough-specific QoL questionnaire (PAC-QoL16) using a different dataset (i.e., different children), (2) confirm the minimally important difference (MID), and (3) develop and validate a short form. METHODS: Three datasets from two sources were utilized, comprising of 332 children with acute cough (< 2 weeks duration); the first dataset (n = 83, 54 boys; median age 2.04 years, IQR 1.08-4.06 years) was used for revalidation, the second dataset (n = 238, 141 boys; median age 2.17 years, IQR 1.21-4.21 years) was used to develop the short form, and the third dataset (n = 94, 62 boys; median age, 1.75 years, IQR 0.90-3.63 years) was used to confirm the short form. Psychometric properties were investigated. RESULTS: Six items were found to account for 96.4% of the variance in the PAC-QoL16. The PAC-QoL16 and short form (PAC-QoL6) scales correlated with cough scores (rs ≤ - 0.40, p < 0.001), were internally consistent (Cronbach α = 0.94 and 0.87, respectively) and demonstrated sensitivity to change over time. A MID of 0.71 to 1.11 is recommended. CONCLUSION: Both the PAC-QoL16 and newly developed short form (PAC-QoL6) are reliable and valid outcome measures that assess children's acute cough-specific QoL at a given time point, are easy to interpret and reflect changes over time. The new short form addresses the need for outcome measures to be as time effective as possible without loss of information.

Minimally important differences for interpreting European Organisation for Research and Treatment of Cancer (EORTC) Quality of life Questionnaire core 30 scores in patients with ovarian cancer.

INTRODUCTION: Minimal important differences (MIDs) are useful for interpreting changes or differences in health-related quality of life scores in terms of clinical importance. There are currently no MID guidelines for the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire core 30 (EORTC QLQ-C30) specific to ovarian cancer. This study aims to estimate MIDs for interpreting group-level change of EORTC QLQ-C30 scores in ovarian cancer. METHODS: Data were derived from four EORTC published trials. Clinical anchors for each EORTC QLQ-C30 scale were selected using correlation strength and clinical plausibility. MIDs for within-group change and between-group differences in change over time were estimated via mean change method and linear regression respectively. For each EORTC QLQ-C30 scale, MID estimates from multiple anchors were summarized via weighted-correlation. Distribution-based MIDs were also examined as supportive evidence. RESULTS: Anchor-based MIDs were determined for deterioration in 7 of the 14 EORTC QLQ-C30 scales assessed, and in 11 scales for improvement. Anchor-based MIDs for within-group change ranged from 4 to 19 (improvement) and - 9 to -4 (deterioration). Between-group MIDs ranged from 3 to 13 (improvement) and - 11 to -4 (deterioration). Generally, absolute anchor-based MIDs for most scales ranged from 4 to 10 points. CONCLUSIONS: Our findings will aid interpretation of EORTC QLQ-C30 scores in ovarian cancer and inform sample size calculations in future ovarian cancer trials with endpoints that are based on EORTC QLQ-C30 scales.

Estimation of an Instrument-Defined Minimally Important Difference in EQ-5D-5L Index Scores Based on Scoring Algorithms Derived Using the EQ-VT Version 2 Valuation Protocols.

OBJECTIVES: To estimate and compare the minimally important difference (MID) in index score of country-specific EQ-5D-5L scoring algorithms developed using EuroQol Valuation Technology protocol version 2, including algorithms from Germany, Indonesia, Ireland, Malaysia, Poland, Portugal, Taiwan, and the United States. METHODS: A simulation-based approach contingent on all single-level transitions defined by the EQ-5D-5L descriptive system was used to estimate the MID for each algorithm. RESULTS: The resulting mean (and standard deviation) instrument-defined MID estimates were Germany, 0.083 (0.022); Indonesia, 0.093 (0.012); Ireland, 0.098 (0.023); Malaysia, 0.072 (0.010); Poland, 0.080 (0.030); Portugal, 0.080 (0.018); Taiwan, 0.101 (0.010); and the United States, 0.078 (0.014). CONCLUSIONS: These population preference-based MID estimates and accompanying evidence of how such values vary as a function of baseline index score can be used to aid interpretation of index score change. The marked consistency in the relationship between the calculated MID estimate and the range of the EQ-5D-5L index score, represented by a ratio of 1:20, might substantiate a rule of thumb allowing for MID approximation in EQ-5D-5L index score warranting further investigation.

Minimally important differences for interpreting the EORTC QLQ-C30 in patients with advanced colorectal cancer treated with chemotherapy.

AIM: The European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) assesses the health-related quality of life of patients in cancer trials. There are currently no minimally important difference (MID) guidelines for the EORTC QLQ-C30 for colorectal cancer (CRC). This study aims to estimate MIDs for the EORTC QLQ-C30 scales in patients with advanced CRC treated with chemotherapy and enrolled in clinical trials. METHOD: The data were obtained from three published EORTC trials that treated CRC patients using chemotherapy. Potential anchors were selected from clinical variables based on their correlation with EORTC QLQ-C30 scales. Anchor-based MIDs for within-group change and between-group change were estimated via the mean change method and linear regression, respectively, and summarized using weighted correlation. Distribution-based MIDs were also examined. RESULTS: Anchor-based MIDs were determined for deterioration in 8 of the 14 EORTC QLQ-C30 scales and in 9 scales for improvement, and varied by scale, direction of change and anchor. MIDs for improvement (deterioration) ranged from 6 to 18 (-11 to -5) points for within-group change and 5 to 15 (-10 to -4) for between-group change. Summarized MIDs (in absolute values) per scale mostly ranged from 5 to 10 points. CONCLUSIONS: These findings have clinical relevance for the interpretation of treatment efficacy and the design of clinical trials by informing sample size requirements.

Validation of the Sexual Activity Questionnaire in women with endometriosis.

STUDY QUESTION: Is the Sexual Activity Questionnaire (SAQ) a valid tool for patients treated for symptomatic endometriosis? SUMMARY ANSWER: For women having surgical treatment for endometriosis, we determined that the SAQ is a valid and responsive tool. WHAT IS KNOWN ALREADY: Endometriosis adversely affects sexual quality of life. Suitable validated sexual quality of life instruments for endometriosis are lacking both in clinical practice and for research. STUDY, DESIGN, SIZE, DURATION: A total of 367 women with proven endometriosis undergoing medical or surgical treatment were included in an observational study conducted between 1 January 2012 and 31 December 2014 in two French tertiary care centers. Both hospitals are reference centers for endometriosis treatment. Of these 367 women, 267 were sexually active and constituted the baseline population. PARTICPANTS/MATERIALS, SETTINGS, METHODS: Women >18 years old with histological or radiological proven endometriosis, consulting for painful symptoms of at least 3 months duration, infertility, or other symptoms (bleeding, cysts) were invited to complete self-administered questionnaires before (T0) and 12 months after treatment (T1). Tests of data quality included descriptive statistics of the data, missing data levels, floor and ceiling effects, structural validity and internal consistency.The construct validity was obtained by testing presupposed relationships between previously established SAQ scores and prespecified characteristics of the patients by comparing different subgroups of patients at T0. Sensitivity to change was subsequently calculated by comparing the SAQ score between T1 and T0 overall and for different subgroups of treatment. Effect sizes (to T1) were calculated according to Cohen's method. The minimally important difference was estimated by a step-wise triangulation approach (including anchor-based method). MAIN RESULTS AND THE ROLE OF CHANCE: In total, 267 sexually active patients (204 surgical and 63 medical treatment) completed the SAQ at T0 and 136 (50.9%) at T1. The SAQ score ranged from 2.0 to 28.0 (mean ± SD: 16.8 ± 5.7).The SAQ score was one-dimensional according to the scree plot with good internal consistency (Cronbach alpha = 0.78, 95% CI 0.74-0.81) and had good discriminative ability according to pain descriptors and quality of life in endometriosis. The SAQ was responsive in patients treated by surgery but the effect size was low (0.3, 95% CI (0.0-0.6), P = 0.01). The minimally important difference was determined at 2.2. LIMITATIONS, REASONS FOR CAUTION: The effect size for medical treatment was non-significant. Other effect sizes were low but statistically significant. This could be explained by lower libido due to progestin intake, which was used for both surgically and medically treated patients. WIDER IMPLICATIONS OF THE FINDINGS: The SAQ is easy to use, valid and effective in assessing sexual quality of life in patients with endometriosis. This patient-reported score could be used as a primary outcome for future clinical studies. The minimally important difference estimation will be useful for future research. We recommend using 2.2 for the minimally important difference of the SAQ. STUDY FUNDING/COMPETING INTEREST(S): This work was funded by the 'Direction à la Recherche Clinique et à l'Innovation' of Versailles, France and the 'Institut de Recherche en Santé de la Femme' (IRSF). The authors have no conflicts of interest to declare.

Determination of the minimally important difference in a nasal symptom score in house dust mite allergy.

BACKGROUND: House dust mite (HDM) allergens are responsible for the most prevalent persistent respiratory allergies. Clinical trials in this field often use a four-component nasal symptom score (T4NSS) as a measure of efficacy. METHODS: The present observational, prospective, multinational, multicenter study determined the minimal important difference (MID) for a T4NSS in children, adolescents, and adults with physician-diagnosed HDM-induced allergic rhinoconjunctivitis (AR). Patients rated the T4NSS daily, a 15-point global rating of change scale (GRCS) and the Rhinoconjunctivitis Quality of Life Questionnaire weekly. The MID was determined primarily by using a regression method with a GRCS threshold of 2. RESULTS: A total of 546 patients (210 adults, 133 adolescents, and 203 children) were included; 92.6% of the patients had moderate-to-severe AR, and 30.1% had concomitant mild asthma. During the first week, the mean ± standard deviation T4NSS was 5.68 ± 2.76 in adults, 5.34 ± 2.66 in adolescents, and 5.07 ± 2.48 in children. In a GRCS regression analysis, the MID [95% confidence interval] for the T4NSS was -0.90 [-1.06;-0.75] overall (n = 509), -0.94 [-1.19;-0.69] in children (n = 187), -0.74 [-1.07;-0.41] in adolescents (n = 125), and -1.04 [-1.29;-0.79] in adults (n = 197). The MID did not differ greatly from one disease severity tertile to another. Confirmatory distribution-based analyses yielded overall MID values of -0.87 for the first week of the study and -0.93 for the week 2-week 1 difference. CONCLUSION: The MID for improvement in the T4NSS is at least -0.90 units in children, adolescents, and adults suffering from HDM-induced AR This value could be rounded up to -1 unit for convenience.

Changes in quality of life in relation to disease activity in systemic lupus erythematosus: post-hoc analysis of the BLISS-52 Trial.

OBJECTIVES: To quantify changes in generic patient-reported outcomes against clinically meaningful, disease activity measures in systemic lupus erythematosus (SLE). METHODS: Using BLISS-52 trial data (867 SLE patients), we estimated the mean difference in change of patient-reported outcome scores (Medical Outcomes Study SF-36 and FACIT-fatigue) in relation to disease activity (SELENA-SLEDAI, SELENA-SLEDAI flare index, SLE responder index and British Isles Lupus Assessment Group (BILAG)), considering all study visits by the mean of multivariate mixed models. Predefined disease activity criteria were used to define for improvement and worsening. RESULTS: Mean changes in physical component summary/mental component summary and FACIT-fatigue in response to changes in SELENA-SLEDAI and SELENA-SLEDAI flare index were significantly lower than 2.5. New SELENA-SLEDAI flare index flare led to a significant change in all patient-reported outcome scores, except role emotional. Mean improvement in patient-reported outcomes with achievement of SLE responder index ranged between +6.2 (physical function) and +11.3 (bodily pain) for SF-36 domains, + 3.4 and +3.3 for mental component summary and physical component summary, and was +4.2 for FACIT-fatigue. When considering disease activity changes by organ system, changes in BILAG (constitutional) was independently associated with significant changes in FACIT-fatigue and all SF-36 domains (except physical function), changes in BILAG (musculoskeletal and hematological) were independently associated with significant changes in patient-reported outcome scores, except for role emotional (musculoskeletal) and general health/mental health (hematological). Mean changes in every SF-36 domain varied (and was >5) with SLE responder index attainment. CONCLUSIONS: Knowledge of changes in patient-reported outcomes, against clinically meaningful changes in SLE disease activity measures, is crucial for designing of clinical trials, interpretation of results and shared decision-making for patient care.

Estimation of minimally important differences and responder definitions for EORTC QLQ-MY20 scores in multiple myeloma patients.

OBJECTIVES: Thresholds for the minimally important difference (MID) or responder definition (RD) in health-related quality-of-life (HRQoL) scores are required to interpret the impact of an intervention or change in the trajectory of the condition which is meaningful to patients. This study aimed to establish MID and RD for the European Organisation for Research and Treatment of Cancer Quality of Life Multiple Myeloma questionnaire (EORTC QLQ-MY20). METHODS: A novel mixed-methods approach was applied by utilizing both existing clinical trial data and prospective patient interviews. Anchor-based, distribution-based, and qualitative-based estimates of meaningful change were triangulated to form recommended RDs for each scale of the EORTC QLQ-MY20. Anchor-based MIDs were summarized using weighted correlation. RESULTS: Recommended MIDs were as follows: Disease Symptoms (DS 10 points), Side Effects of Treatment (SE 10 points), Body Image (BI 13 points), and Future Perspective (FP 9 points). Recommended RDs were as follows: DS (16 improvement; 11 worsening), SE (6 improvement; 9 worsening), BI (33 improvement; 33 worsening), and FP (11 improvement; 11 worsening). CONCLUSIONS: The study generated estimates of the MID and RD for each scale of the EORTC QLQ-MY20. Published estimates will enable investigators and clinicians to adopt these as standard for interpretation and for hypothesis testing. Consequently, analyses from trials of different interventions can be more comparable.

Minimally important difference and predictors of change in quality of life in type 2 diabetes: A community-based survey in China.

BACKGROUND: To identify the minimally important difference (MID) of the EQ-5D-3L and determinants of change in quality of life (QoL) as measured by the EQ-5D-3L over 1 year for Chinese type 2 diabetic patients (T2DPs). METHODS: Clinically diagnosed T2DPs were recruited from 66 community health centres in five Chinese cities using a multistage quota sampling method between December 2010 and October 2011. Demographics, diabetes-related information, and health-related behaviours were collected at baseline. The EQ-5D-3L was administered at baseline and at 12 months. Anchor-based and distribution-based approaches were employed to estimate MIDs. Using the MIDs as cut-points, we identified the change in EQ-5D-3L-measured QoL into "worsening," "no change," and "bettering." Logistic and ordered logistic regressions were conducted for those who reported best possible EQ-5D health state ("best possible HS") and impaired EQ-5D health states ("impaired HS") at baseline, respectively. Explanatory variables included demographics, diabetes-related information, and health-related behaviours. RESULTS: A total of 1958 patients (54.9% female, mean age 61.2 years, mean diabetes duration 7.9 years) were included in our analysis. MIDs of the EQ-5D-3L for deterioration and improvement were estimated as -0.066 to -0.003, and 0.049 to 0.077, respectively. For the impaired HS group, older age, lower education, and less exercise were significant predictors for worsening in QoL; whereas, those predictors were older age, female gender, and lower income for the best possible HS group. CONCLUSIONS: Minimally important differences for deterioration and improvement were estimated for the EQ-5D-3L. Age, gender, education, income, and exercise were significant determinants of QoL change for Chinese T2DPs.