Methods of calculation, anchor characteristics, and scaling of MCID calculation in included articles (n = 36).
| Total, n = 36 | RA, n = 17 | OA Knee and Hip, n = 4 | OA Knee, n = 12 | OA Hip, n = 5 | OA Hand, n = 1 | |
|---|---|---|---|---|---|---|
| Calculation method | ||||||
| Distribution only | 1 (2.8%) | 1 (6%) | ||||
| Anchor only | 16 (44.4%) | 7 (41%) | 3 (75%) | 3 (25%) | 3 (60%) | 1 (100%) |
| Distribution and anchor | 19 (52.8%) | 9 (53%) | 1 (25%) | 9 (75%) | 2 (40%) | |
| Articles with anchor | ||||||
| External patient anchor | 27 (75%) | 8 (47%)‡ | 4 (100%) | 12 (100%) | 5 (100%) | 1 (100%) |
| Other internal anchors (non-patient derived) | 8 (22.2%) | 8 (47%) | ||||
| External patient anchor properties | ||||||
| No. of level of response (range) | 3 to 15 | 3 to 7 | 5 to 15 | 3 to 15 | 3 to 5 | 8 |
| Time frame of anchor (range) | 2 wks to 5 yrs | 2 wks to 1 yr | 2 wks to 3 mos | 4 wks to 5 yrs | 4 wks to 1 yr | 2 wks to 4 wks |
| Multiple recall points | 5 (13.9%) | 1 (6%) | — | 3 (25%) | — | 1 (100%) |
| Scaling | ||||||
| Ordinal | 35 (97.2%) | 16 (94%) | 4 (100%) | 12 (100%) | 5 (100%) | 1 (100%) |
| Interval | 1 (2.8%) | 1 (6%) | — | — | — | — |
| PROM | ||||||
| WOMAC | 11 (31%) | 2 (50%) | 7 (58%) | 4 (80%) | — | |
| SF36 | 10 (28%) | 5 (29%) | 1 (25%) | 4 (33%) | 1 (20%) | — |
| FACIT | 3 (8%) | 3 (18%) | — | — | — | — |
| HAQ | 8 (22%) | 8 (47%) | — | — | — | — |
| Others | 20 (56%) | 12 (71%) | 2 (50%) | 7 (58%) | 2 (40%) | 1 (100%) |
↵‡ 2 of 8 were group conversations. n: number of articles; PROM: patient-reported outcome measures; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index; SF-36: Medical Outcomes Study Short Form-36; FACIT-F: Functional Assessment of Chronic Illness Therapy–Fatigue; HAQ: Health Assessment Questionnaire.