Table 3. Change Within Groups and Difference in Change Between Groups for Continuous Outcomes, Using Multiply Imputed Data.
| Outcome measuresa | Change within groups, mean (SD) | Difference in change between groupsb | ||
|---|---|---|---|---|
| Baseline minus week 24 | Baseline to week 24 | |||
| Intervention (n = 103) | Control (n = 103) | Mean difference (95% CI) | P value | |
| Primary outcomes | ||||
| Overall average knee pain (NRS)c | 2.8 (2.1) | 1.2 (2.2) | 1.6 (0.9 to 2.2) | <.001 |
| Physical function (WOMAC)d | 10.1 (10.8) | 4.4 (11.9) | 5.2 (1.9 to 8.5) | .002 |
| Secondary outcomes | ||||
| Pain (KOOS)d | −18.5 (15.3) | −6.4 (15.9) | −11.3 (−15.7 to −7.0) | <.001 |
| Sport and recreation (KOOS)d | −16.9 (22.2) | −8.4 (22.8) | −9.1 (−15.3 to −2.9) | .004 |
| Knee-related quality of life (KOOS)d | −15.3 (19.6) | −8.2 (17.8) | −7.4 (−12.6 to −2.2) | .005 |
| Health-related quality of life (AQoL)d | −0.07 (0.16) | −0.00 (0.14) | −0.07 (−0.11 to −0.02) | .002 |
| Physical activity levels (PASE)d | −14.0 (67.1) | −9.6 (78.7) | −9.6 (−29.8 to 10.5) | .35 |
| Self-efficacy (ASES)d | ||||
| Pain | −0.7 (2.6) | −0.0 (1.9) | −0.6 (−1.3 to −0.0) | .046 |
| Function | −0.3 (2.2) | −0.2 (1.3) | 0.0 (−0.4 to 0.5) | .89 |
| Self-efficacy exercise (SEE) | 4.8 (23.5) | 6.2 (19.5) | −2.4 (−7.9 to 3.1) | .39 |
| Treatment satisfactionc | NA | NA | 1.2 (0.7 to 1.6) | <.001 |
Abbreviations: AQoL, Assessment of Quality of Life; ASES, Arthritis Self-Efficacy Scale; KOOS, Knee Injury and Osteoarthritis Outcome score; NA, not applicable; NRS, numeric rating scale; PASE, Physical Activity Scale for the Elderly; SEE, Self-Efficacy for Exercise; WOMAC, Western Ontario and McMaster Universities Osteoarthritis Index.
Instruments and scoring ranges: AQoL, −0.04 to 1.0, with higher scores indicating better quality of life; ASES function subscale, 1-10, with higher scores indicating greater self-efficacy; ASES pain subscale, 1-10, with higher scores indicating greater self-efficacy; KOOS, 0-100, with lower scores indicating worse pain/symptoms/function/quality of life; NRS, 0-10 with higher scores indicating worse pain; PASE, 0-400+, with higher scores indicating more activity; SEE scale, 0-90, with high scores indicating greater self-efficacy; treatment satisfaction, 1-7, with higher scores indicating greater treatment satisfaction; and WOMAC physical function subscale, 0-68, with higher scores indicating worse function.
Adjusted for baseline value of outcome where possible.
For change within groups, positive changes indicate improvement. For difference in change between groups, positive differences favor the intervention.
For change within groups, negative changes indicate improvement. For difference in change between groups, negative differences favor the intervention.