Cross-cultural adaptation and preliminary validation of the Korean version of the Psoriatic Arthritis Impact of Disease-12 questionnaire

BACKGROUND/AIMS: The Psoriatic Arthritis Impact of Disease (PsAID-12) questionnaire was developed to measure quality of life and disease impact in patients with psoriatic arthritis (PsA). We aimed to translate the English PsAID-12 into Korean and to evaluate its reliability and validity. METHODS: The PsAID-12 questionnaire was translated into Korean following international cross-cultural adaptation guidelines. After expert review and cognitive debriefing with 10 patients, the final Korean version of the PsAID-12 was established. For validation, 21 patients with PsA completed the Korean PsAID-12 questionnaire, and a retest was conducted one week later to assess reliability. Demographic data and disease activity indices, including the Disease Activity in Psoriatic Arthritis (DAPSA) and Visual Analog Scale (VAS) pain were collected. Correlations between PsAID-12 scores and disease activity indices were analyzed. RESULTS: Minor discrepancies in the translation process were resolved during the synthesis and review. The mean PsAID-12 scores were 3.9 ± 2.6 and 3.6 ± 2.3 for the first and second assessments, respectively. The mean response time was 2.6 ± 1.0 min. The intraclass correlation coefficient was 0.856 (95% CI 0.682-0.939, p < 0.050), indicating good reliability. The first PsAID-12 score was strongly correlated with the second PsAID-12 (r = 0.79), DAPSA (r = 0.66), and VAS pain (r = 0.67). CONCLUSION: The Korean PsAID-12 questionnaire was well translated and validated, showing strong reliability and correlation with disease activity measures. It is therefore appropriate for assessing the impact of PsA in Korean patients.