Measuring psoriatic arthritis symptoms: A core domain in psoriasis clinical trials

The International Dermatology Outcome Measures established a set of core domains to be measured in all psoriasis trials. This set requires that symptoms of psoriatic arthritis (PsA) be measured in all psoriasis studies.

To identify the approach to PsA screening and the most appropriate outcome measure for capturing PsA symptoms.

Following guidelines (ie, the COnsensus-based Standards for the selection of health Measurement INstruments, Core Outcome Measures in Effectiveness Trials Initiative, and Outcome Measures in Rheumatology Handbook), we conducted a consensus-building study that included patients, physicians, industry partners, and patient association representatives. The process consisted of a literature review and quality appraisal of measures for PsA symptoms, a pre-Delphi exercise, a Delphi survey, and a consensus meeting.

Among the 297 expert participants in the Delphi survey, 87.5% agreed that all patients in a psoriasis trial should be screened for PsA with a validated screening tool. Regarding the measurement of PsA symptoms, the preferred instrument was the Psoriatic Arthritis Impact of Disease-9 (PsAID9), with the Routine Assessment Patient Index Data-3 (RAPID3) representing an acceptable alternative.

Only International Dermatology Outcome Measures members participated in the consensus meeting.

The overwhelming majority of expert stakeholders agreed that all psoriasis trial participants should be screened for PsA, with PsA symptoms measured by using PsAID9 (or alternatively with RAPID3).