Health Assessment Questionnaire-Disability Index (HAQ-DI)
PsA
This index consists of 20 items, ordered into eight domains to investigate the limitations in performing daily physical activities. The highest item score within each category is used as the score for that category. Finally, the scores for the categories are averaged to construct a single total score ranging from 0 (no disability) to 3 (completely disabled). This scale has been widely used in patients with PsA, both in the literature and in clinical settings [