Table 3.
Secondary outcomes at baseline and follow-up and mean difference over time between groups
|
Minimum intervention strategy
|
Usual care
|
||||
|---|---|---|---|---|---|
| Measurement | Median (IQR) or mean (SD) | No | Median (IQR) or mean (SD) | No | Mean difference*(95% CI) |
| Pain severity during day (0-10) | |||||
| Baseline
|
5 (3-7)
|
142
|
5 (3-6)
|
171
|
0.015 (−0.41 to 0.44) |
| 6 weeks
|
2 (0-4)
|
141
|
2 (0-4)
|
162
|
|
| 13 weeks
|
0 (0-3)
|
140
|
1 (0-3)
|
164
|
|
| 26 weeks
|
0 (0-3)
|
135
|
0 (0-2)
|
163
|
|
| 52 weeks | 0 (0-3) | 132 | 0 (0-2) | 155 | |
| Severity of main complaint (0-10) | |||||
| Baseline
|
7 (5-8)
|
142
|
7 (5-8)
|
170
|
0.021 (−0.45 to 0.49) |
| 6 weeks
|
2 (0-5)
|
142
|
2 (0.5-4)
|
161
|
|
| 13 weeks
|
1 (0-3.25)
|
138
|
1 (0-3)
|
164
|
|
| 26 weeks
|
1 (0-4)
|
135
|
1 (0-3)
|
160
|
|
| 52 weeks | 1 (0-3) | 132 | 1 (0-3) | 153 | |
| Perceived general health (SF-36, 1-5) | |||||
| Baseline
|
2.7 (0.8)
|
143
|
2.8 (0.8)
|
169
|
0.056 (−0.07 to 0.17) |
| 6 weeks
|
-
|
|
-
|
|
|
| 13 weeks
|
2.6 (0.8)
|
136
|
2.6 (0.8)
|
154
|
|
| 26 weeks
|
2.6 (0.7)
|
132
|
2.6 (0.8)
|
154
|
|
| 52 weeks | 2.7 (0.9) | 131 | 2.7 (0.8) | 153 | |
IQR=interquartile range; SF-36=short form 36 (higher scores mean worse health; not assessed after six weeks' follow-up).
*
Minimal intervention strategy (MIS) minus usual care (UC), adjusted for baseline values and estimated with multilevel analysis. Mean difference >0 means that over 12 months MIS group had higher mean score on that outcome measure than UC group (that is, more pain, greater severity of main complaint, and worse health).