Evidence for inadequate construct validity of the Disease Repercussions Profile in people with rheumatoid arthritis

OBJECTIVE: To re-evaluate the construct validity of the Disease Repercussions Profile (DRP), a measure of handicap in arthritis populations. METHODS: We used the multitrait-multimethod approach to determine convergent and discriminant validity in a postal survey of randomly selected patients with rheumatoid arthritis who had attended the Wellington Regional Rheumatology Unit since 1988. Respondents (n=142) completed the following self-report instruments: Disease Repercussions Profile, EuroQol EQ-5D, Health Assessment Questionnaire, London Handicap Scale and WHOQOL-BREV. RESULTS AND CONCLUSIONS: The pattern of correlation supported the construct validity of the dichotomous response question (DRP domain affected or not) for the activity and relationships domain, provided ambiguous support for the appearance and emotion domain and no support for the social and financial domains. There was no support for construct validity of any of the domains on the importance rating part of the DRP. We suggest that the DRP be interpreted cautiously in aggregated group data.