Development of an instrument for patient self-assessment in psoriatic arthritis

Objective Due to the recent pandemic, in person scheduled rheumatology appointments in many countries have been reserved for urgent cases only. Here we report the development of a multidimensional, patient completed disease assessment tool for use in psoriatic arthritis (PsA).

Methods A focus group development and education method was used, followed by a paired observation design to assess feasibility and validity. The psoriatic arthritis disease activity score (PASDAS) was used as the basis for the clinical assessments but elements of this tool were modified during the focus group sessions.

Results A preliminary tool assessed tender and swollen joint counts, enthesitis, dactylitis, area of skin involved by psoriasis, and scores for global disease activity, fatigue and spinal pain. In parallel assessments good agreement was found between subject and health professional assessors, though overall disease activity was low.

Conclusion A self-assessment tool for disease activity in psoriatic arthritis has been developed in conjunction with patients demonstrating generally good agreement between patients and health professionals but more validation work is needed before it can be recommended for clinical practice.