Translation and validation of Portuguese of a questionnaire for evaluation of psychosomatic symptoms in adults with atopic dermatitis

The Dermatology Life Quality Index (DLQI) used as the benchmark in validation of 101 quality-of-life instruments: A systematic review

BACKGROUND

The validation of psychometric measures requires use of other established and standardized validated measures. The Dermatology Life Quality Index (DLQI) is the most widely used tool to measure the burden of skin diseases and assess effectiveness of interventions based on patients' perspective.

OBJECTIVES

The objective of this study was to systematically analyse peer-reviewed publications describing use of the DLQI in validation of other patient-reported outcome (PRO) and quality-of-life (QoL) measures.

METHODS

Seven databases were searched for papers published between January 1994 and December 2022 for articles containing data using DLQI in the validation of other PRO/QoL measures. The methodology followed PRISMA guidelines. The protocol was prospectively registered on PROSPERO.

RESULTS

Of 1717 screened publications, 122 articles including 30,727 patients from 34 different countries with 41 diseases met the inclusion criteria. The DLQI was used in validation of 101 measures: 80 dermatology-specific QoL measures, mostly disease-specific, and 21 generic measures. Of these studies, 47 were cross-cultural adaptations, 116 single arm, 100 were cross-sectional, 18 longitudinal and six randomized placebo controlled. DLQI was used for 14 known group, and correlation for 10 construct, 101 convergent, 10 concurrent, 10 divergent/discriminant and three criterion validity tests using Mann-Whitney (2), Spearman's (80), Pearson's correlation (26) and Student's t-test (1). The DLQI was used in responsiveness analysis in 13 studies.

CONCLUSIONS

This review identified widespread use of the DLQI in validation of other dermatology PRO/QoL measures and confirmed the central role that the DLQI plays as a benchmark in instrument development and validation across dermatology and beyond. The use of the DLQI by so many developers of other instruments has provided a common standard for comparability.

Differences in Psychometric Properties of Clinician- and Patient-Reported Outcome Measures for Atopic Dermatitis by Race and Skin Tone: A Systematic Review

The psychometric validity and reliability of widely used atopic dermatitis (AD) outcome measures across different races and ethnicities are unclear. We describe the rates of reporting race, ethnicity, and skin tone in studies testing the psychometric properties of AD outcome measures and compare the psychometric analyses across race, ethnicity, and skin tone. We systematically reviewed MEDLINE and EMBASE for studies reporting psychometric properties of clinician-reported or patient-reported outcome measures in AD (International Prospective Register of Systematic Reviews: CRD42021239614). Overall, 16,100 nonduplicate articles were screened; 165 met inclusion criteria. Race and/or ethnicity were reported in 55 (33.3%) studies; of those, race was assessed by self-report in 10 studies (6.1%) or was unspecified in 45 (27.3%). A total of 16 studies (9.7%) evaluated psychometric property differences by race, and only five (4.4%) of those did not recognize it as a limitation. Properties assessed across race, ethnicity, or skin tone were differential item functioning, convergent validity feasibility, inter-rater reliability, intrarater reliability, test‒retest reliability, and known-groups validity. Multiple instruments demonstrated performance differences across ethnoracial groups. This review highlights the paucity of race/ethnicity consideration for psychometric property testing in AD outcome measurement instruments. More AD outcomes instruments should be validated in diverse populations.