Composite measure specific to PsA.
| Measure | Domains | No. Items | Reliability | Validity | Considerations |
|---|---|---|---|---|---|
| PsARC89,90 | TJC, SJC, PGA, PtGA | 4 | Not assessed | Chi-square = 19.3–27.9 | Does not include enthesitis, dactylitis, or skin disease assessment |
| PsAJAI91,92 | TJC, CRP, PGA, pain, PtGA, HAQ | 6 | Not determined | Not assessed | Does not include enthesitis, dactylitis, or skin disease assessment |
| DAPSA93,94 | TJC, SJC, PtGA, pain, CRP | 5 | Not determined | The instrument correlated highly with other measures, including the DAS, SDAI, and CDAI | |
| CPDAI95 | Peripheral joints, skin, enthesitis, dactylitis, and spinal manifestations* | 5 | Not assessed | The CPDAI demonstrates significant correlation with PtGA (r = 0.777) and PGA (r = 0.809) assessments and discriminates well between effectively and ineffectively treated patients | More sensitive than other instruments to detect change in domains beyond joints and patient’s global, particularly in domains such as enthesitis, dactylitis, and the skin, which are important multidimensional components of PsA |
| PASDAS | TJC, SJC, PGA, PtGA, SF36 PCS, enthesitis, dactylitis, CRP | 8 | Correlation with other measures | More sensitive than other instruments to detect change in disease activity | |
| GRACE index | SJC, TJC, VAS patient’s global, VAS skin, VAS joints, HAQ, PASI, PsAQoL | 8 | Correlation with other measures | As sensitive as other instruments to detect change in disease activity |
↵* For each domain, individual instruments were used to assess the extent of disease activity as well as the effect on patient function and health-related quality of life. PsA: psoriatic arthritis; PsARC: Psoriatic Arthritis Response Criteria; PsAJAI: Psoriatic Arthritis Joint Activity Index; DAPSA: Disease Activity in Psoriatic Arthritis; CPDAI: Composite Psoriatic Disease Activity Index; PASDAS: Psoriatic Arthritis Disease Activity Score; TJC: tender joint count; SJC: swollen joint count; PGA: physician’s global assessment; PtGA: patient’s global assessment; CRP: C-reactive protein; HAQ: Health Assessment Questionnaire; SF-36 PCS: Medical Outcomes Study Short Form-36 physical component summary; VAS: visual analog scale; PASI: Psoriasis Area and Severity Index; PsAQoL: Psoriatic Arthritis Quality of Life; DAS: Disease Activity Score; SDAI: Simple Disease Activity Index; CDAI: Clinical Disease Activity Index.