Analysis of direct between-group comparison (I vs C) of mean change at 6 months and standardized effect size (SES).
| Outcome | Mean Change Score (SD) (6 months – baseline) | SES 1 vs C | |
|---|---|---|---|
| Intervention (I) | Waitlist Control (C) | ||
| Primary | |||
| Arthritis self-efficacy | 1.06 (1.51) | −0.04 (2.11) | 0.6 |
| Secondary | |||
| Previous knowledge (ACREU RA) | 2.26 (2.51) | 0.58 (3.29) | 0.6 |
| RxEd content knowledge | 1.74 (2.45) | 0.42 (2.93) | 0.5 |
| Coping efficacy | 0.45 (0.75) | 0 (0.64) | 0.7 |
| Illness intrusiveness | 5.0 (15.46) | −2.93 (9.97) | 0.6 |
Positive change score = better; negative change score = worse; SES = ratio of treatment effect (mean change in I group – mean change in C group) to pooled standard deviation of these differences25. ACREU: The Arthritis Community Research and Evaluation Unit; RA: rheumatoid arthritis; RxEd: Prescription for Education program.