Table 5.
Subgroup analyses: treatment effects within two STarT Back risk groups
| Primary outcomes | STarT-G score at baseline (0–3) (low risk of back pain chronification) |
STarT-G score at baseline > 3 (= medium or high risk of back pain chronification) | |||||||
|---|---|---|---|---|---|---|---|---|---|
| IG (N = 100) M + (95% CI) |
CG (N = 162) M + (95% CI) |
Between group effects | IG (N = 89) M + (95% CI) |
CG (N = 93) M + (95% CI) |
Between group effects | ||||
| p | Cohen’s d * [95% CI] |
p | Cohen’s d * [95% CI] |
||||||
| Back pain severity (CPGQ) | pain intensity (0–100) | 33.3 (29.9–36.7) | 32.3 (29.6–34.9) | 0.632 | 0.06 (−0.19 to 0.31) | 47.5 (43.8–51.3) | 54.9 (51.2–58.6) | 0.007 | −0.41(− 0.70 to − 0.11) |
| disability points (0–6) | 1.1 (0.8–1.4) | 1.1 (0.9–1.4) | 0.778 | 0 (− 0.25 to 0.25) | 2.5 (2.1–2.9) | 3.2 (2.8–3.5) | 0.018 | − 0.36(− 0.65 to − 0.06) | |
| Health- related quality of life (SF-12) | physical component (0–100) | 46.3 (44.6–48.1) | 45.4 (44.1–46.8) | 0.416 | 0.10 (− 0.15 to 0.35) | 38.5 (36.6–40.3) | 34.6 (32.8–36.5) | 0.005 | 0.43 (0.13 to 0.72) |
| mental component (0–100) | 48.0 (46.2–49.9) | 50.1 (48.6–51.5) | 0.090 | −0.22 (− 0.47 to 0.03) | 44.7 (42.4–46.9) | 41.9 (39.7–44.1) | 0.094 | 0.25 (− 0.04 to 0.55) | |
IG intervention group, CG control group, p significance value, M +: values of the group means adjusted for baseline-score, StarT-G total risk score and satisfaction with medical care of back pain at baseline, CI Confidence interval, CPGQ Chronic Pain Grade Questionnaire; SF-12: Short From 12
Cohen’s d*: if higher scores of the outcome parameter describe worse health condition (GCPS-parameters), minus d means IG is superior to CG and plus d means IG is worse than CG; if higher scores describe better health conditions (SF-12 parameters), minus d signifies IG is inferior to CG and plus d means IG is better than CG