Which Outcomes Should We Measure in Vitiligo?
Background Relevant and reliable outcomes play a crucial role in the correct interpretation and comparison of the results of clinical trials. There is a lack of consensus around methods of assessment and outcome measures for vitiligo, which makes it difficult to compare results of randomized controlled trials (RCTs) and perform meta-analysis.
Objectives To describe the heterogeneity in outcome measures used in published RCTs of vitiligo treatments, and to report the most desirable outcomes from patients' and clinicians' perspectives.
Methods We conducted a systematic review of outcome measures used in RCTs as well as a survey of the most desirable outcomes identified by patients and clinicians as part of a Vitiligo Priority Setting Partnership.
Results Outcomes from 54 eligible trials were analysed and compared with outcomes suggested by patients and clinicians. In the systematic review, 25 different outcomes were reported. Only 22% of trials had clearly stated primary outcome measures. Repigmentation was the most frequently reported outcome in 96% of trials and was measured using 48 different scales. Only 9% of trials assessed quality of life. Thirteen per cent measured cessation of spreading of the disease and 17% of studies reported patients' opinions and satisfaction with the treatment. In contrast, out of 438 suggestions made by patients and clinicians, cosmetically acceptable repigmentation (rather than percentage of repigmentation) was the most desirable outcome (68%), followed by cessation of spread of vitiligo (15%), quality of life (8%) and maintenance of repigmentation (4%).
Conclusions We propose that future vitiligo trials should include repigmentation, cosmetic acceptability of results, global assessment of the disease, quality of life, maintenance of repigmentation, stabilization of vitiligo and side-effects. International consensus among clinicians, researchers and patients is needed to establish an agreed core outcome set for future vitiligo trials.
Vitiligo is the most common chronic skin depigmentation disorder, affecting around 0·5% of the world population. The causes of vitiligo are still poorly understood and treatment is often unsatisfactory.
Recently, it has been proposed that 'core outcomes' should be agreed among researchers, to be measured and reported in all trials in order to allow the results of trials to be compared and combined in meta-analyses (COMET Initiative) This does not imply that outcomes in a particular study should be restricted to the core outcomes only, but rather that the core outcomes should be collected and reported alongside others that researchers feel are important.
There is currently a lack of consensus in the definition and methods of assessment of vitiligo which makes it difficult to perform meta-analyses or to compare the outcomes of different studies. Although a new international consensus definition and classification of vitiligo has been proposed, consensus of the measurement of disease response is still unclear. Over a period of 43 years, 68 different single or combination interventions have been evaluated in 57 randomized controlled trials (RCTs). An updated Cochrane systematic review published in 2010 concluded that most studies differ greatly in the ways in which vitiligo is measured and in the myriad combinations of interventions assessed. The heterogeneity of studies in the review made it impossible to combine trial results in meta-analyses.
In clinical trials the selection of appropriate outcomes, which are relevant to patients and those making decisions about healthcare, is crucial to the assessment of whether one intervention is better than another. Vitiligo is a cosmetically and psychologically devastating disease causing great distress, embarrassment and difficulties in relationships. Therefore, one would expect that subjective perception of the disease (i.e. patients' views on the effectiveness of a treatment) would be considered important. However, patient-centred outcomes have rarely been included in vitiligo trials, despite previous recommendations for inclusion in studies on vitiligo and other dermatological conditions.
Therefore, it is important to create consensus among researchers to ensure that the outcomes used in the trials for vitiligo treatment are reliable, clinically relevant and important to both clinicians and patients.
The main aim of this study was to extract and report all the outcomes reported in RCTs of vitiligo treatments and to compare these with the outcomes that patients and clinicians considered to be important.
The secondary objectives were to investigate: (i) what scales were used to measure these outcomes, (ii) methods of assessment of these outcomes and (iii) whether patients' views and their subjective perception of the treatment effectiveness were incorporated in the reported outcomes.
This is a first step towards developing recommendations for outcomes to be used in future trials of treatments for vitiligo.
Abstract and Introduction
Abstract
Background Relevant and reliable outcomes play a crucial role in the correct interpretation and comparison of the results of clinical trials. There is a lack of consensus around methods of assessment and outcome measures for vitiligo, which makes it difficult to compare results of randomized controlled trials (RCTs) and perform meta-analysis.
Objectives To describe the heterogeneity in outcome measures used in published RCTs of vitiligo treatments, and to report the most desirable outcomes from patients' and clinicians' perspectives.
Methods We conducted a systematic review of outcome measures used in RCTs as well as a survey of the most desirable outcomes identified by patients and clinicians as part of a Vitiligo Priority Setting Partnership.
Results Outcomes from 54 eligible trials were analysed and compared with outcomes suggested by patients and clinicians. In the systematic review, 25 different outcomes were reported. Only 22% of trials had clearly stated primary outcome measures. Repigmentation was the most frequently reported outcome in 96% of trials and was measured using 48 different scales. Only 9% of trials assessed quality of life. Thirteen per cent measured cessation of spreading of the disease and 17% of studies reported patients' opinions and satisfaction with the treatment. In contrast, out of 438 suggestions made by patients and clinicians, cosmetically acceptable repigmentation (rather than percentage of repigmentation) was the most desirable outcome (68%), followed by cessation of spread of vitiligo (15%), quality of life (8%) and maintenance of repigmentation (4%).
Conclusions We propose that future vitiligo trials should include repigmentation, cosmetic acceptability of results, global assessment of the disease, quality of life, maintenance of repigmentation, stabilization of vitiligo and side-effects. International consensus among clinicians, researchers and patients is needed to establish an agreed core outcome set for future vitiligo trials.
Introduction
Vitiligo is the most common chronic skin depigmentation disorder, affecting around 0·5% of the world population. The causes of vitiligo are still poorly understood and treatment is often unsatisfactory.
Recently, it has been proposed that 'core outcomes' should be agreed among researchers, to be measured and reported in all trials in order to allow the results of trials to be compared and combined in meta-analyses (COMET Initiative) This does not imply that outcomes in a particular study should be restricted to the core outcomes only, but rather that the core outcomes should be collected and reported alongside others that researchers feel are important.
There is currently a lack of consensus in the definition and methods of assessment of vitiligo which makes it difficult to perform meta-analyses or to compare the outcomes of different studies. Although a new international consensus definition and classification of vitiligo has been proposed, consensus of the measurement of disease response is still unclear. Over a period of 43 years, 68 different single or combination interventions have been evaluated in 57 randomized controlled trials (RCTs). An updated Cochrane systematic review published in 2010 concluded that most studies differ greatly in the ways in which vitiligo is measured and in the myriad combinations of interventions assessed. The heterogeneity of studies in the review made it impossible to combine trial results in meta-analyses.
In clinical trials the selection of appropriate outcomes, which are relevant to patients and those making decisions about healthcare, is crucial to the assessment of whether one intervention is better than another. Vitiligo is a cosmetically and psychologically devastating disease causing great distress, embarrassment and difficulties in relationships. Therefore, one would expect that subjective perception of the disease (i.e. patients' views on the effectiveness of a treatment) would be considered important. However, patient-centred outcomes have rarely been included in vitiligo trials, despite previous recommendations for inclusion in studies on vitiligo and other dermatological conditions.
Therefore, it is important to create consensus among researchers to ensure that the outcomes used in the trials for vitiligo treatment are reliable, clinically relevant and important to both clinicians and patients.
The main aim of this study was to extract and report all the outcomes reported in RCTs of vitiligo treatments and to compare these with the outcomes that patients and clinicians considered to be important.
The secondary objectives were to investigate: (i) what scales were used to measure these outcomes, (ii) methods of assessment of these outcomes and (iii) whether patients' views and their subjective perception of the treatment effectiveness were incorporated in the reported outcomes.
This is a first step towards developing recommendations for outcomes to be used in future trials of treatments for vitiligo.
SHARE
