Evaluating the Persian versions of two psoriatic arthritis screening questionnaires early arthritis for psoriatic patients questionnaire (EARP) and psoriasis epidemiology screening tool (PEST) in Iranian psoriatic patients

The majority of psoriatic arthritis (PsA) patients present at dermatology clinics with cutaneous psoriasis up to 10 years prior to arthritis onset; therefore, applying a suitable screening tool to detect PsA early is essential for dermatologists. This study aimed to validate and evaluate the Persian version of two PsA screening questionnaires, the early arthritis for psoriatic patients questionnaire (EARP) and the psoriasis epidemiology screening tool (PEST) in Iranian psoriatic patients. In this cross-sectional study, psoriatic patients who presented to the dermatology clinic without a previously established PsA were asked to fill out the Persian version of EARP and PEST. PsA was diagnosed by a rheumatologist based on the fulfillment of the classification criteria for psoriatic arthritis. Receiver operator characteristic (ROC) curves, sensitivity, and specificity were calculated for both questionnaires. A total of 75 patients (33 [44%] female, 42 [56%] male, with a mean age of 43.2 ± 14.6) were enrolled in the study. The prevalence of PsA based on rheumatologist diagnosis was 25.3% (19 patients had PsA). The ROC curve analysis of EARP and PEST were 0.949 (95% CI: 0.897–1) and 0.922 (95% CI: 0.834–1). The sensitivity of EARP and PEST questionnaires was 94.7% and 58%, respectively, while the specificity was 78.6% and 96.4%, respectively, with a cut-off of 3. The Persian version of both questionnaires showed good performance. We suggest EARP as a screening tool for PsA in the dermatology clinics due to much higher sensitivity with acceptable specificity compared to PEST.