Control Mean (SD) Range | Intervention Mean (SD) Range | Mean (95% CI) between group difference Control–intervention | Cohen’s d
Effect size Mean difference Intervention–control | |
QBPDS – disability | ||||
Baseline | 41.6 (15.1) 19–78 | 44.3 (12.4) 20–72 | −2.6 (−9.0 to 3.7) | |
Post-treatment | 34.0 (15.8) 6–65 | 22.9 (15.6) 0–54 | 11.1* (3.8 to 18.3) | −1.02 |
4 months | 34.0 (16.9) 7–74 | 21.5 (14.5) 0–54 | 12.9* (5.6 to 20.1) | |
12 months | 31.9 (17.6) 3–74 | 20.3 (16.1) 0–59 | 11.6* (3.6 to 19.5) | |
NRS – pain intensity | ||||
Baseline | 6.4 (1.5) 4–10 | 6.5 (1.6) 3–9 | 0.0 (-0.7 to 0.7) | |
Post-treatment | 5.5 (1.8) 2–8 | 3.2 (1.8) 1–8 | 2.3* (1.4 to 3.1) | −1.45 |
4 months | 5.5 (2.1) 2–9 | 3.2 (1.9) 0–7 | 2.3*(1.4 to 3.2) | |
12 months | 5.3 (2.0) 1–9 | 3.1 (1.9) 0–7 | 2.1* (1.2 to 3.1) | |
SF-36 – quality of life | ||||
Baseline | 49.8 (19.0) 12–84 | 53.2 (16.1) 21–86 | −3.4 (-11.5 to 4.7) | |
Post-treatment | 49.8 (18.9) 19–85 | 65.6 (17.6) 22–91 | −15.8* (−24.2 to –7.4) | 0.8 |
4 months | 50.8 (17.7) 21–81 | 67.7 (17.6) 30–93 | −17.7* (−26.0 to –9.5) | |
12 months | 52.4 (18.2) 23–84 | 71.8 (16.3) 36–95 | −19.5* (−27.9 to–11.0) | |
PSEQ – self-efficacy | ||||
Baseline | 38.9 (13.0) 6–60 | 39.2 (10.2) 12–58 | −0.3 (-5.7 to 5.1) | |
Post-treatment | 39.4 (12.8) 7–60 | 48.5 (9.6) 24–60 | −9.1* (−14.3 to –3.9) | 0.7 |
4 months | 40.5 (12.2) 8–60 | 48.6 (9.2) 22–60 | −8.4* (−13.4 to –3.4) | |
12 months | 38.6 (10.7) 19–55 | 50.5 (7.7) 32–60 | −11.5* (−16.1 to –6.9) | |
TSK | ||||
Baseline | 39.9 (9.3) 22–61 | 36.6 (7.5) 24–55 | 3.3 (-0.6 to 7.2) | |
Post-treatment | 39.4 (8.3) 22–61 | 29.3 (6.9) 17–46 | 10.0* (6.5 to 13.6) | −0.93 |
4 months | 39.3 (8.1) 25–61 | 30.0 (5.3) 20–45 | 9.3* (6.2 to 12.5) | |
12 months | 37.3 (8.0) 24–58 | 31.2 (7.9) 18–54 | 6.1* (−9.9 to –2.3) | |
DASS – depression | ||||
Baseline | 10.7 (11.3) 0–42 | 7.9 (8.1) 0–32 | 2.7 (-1.8 to 7.3) | |
Post-treatment | 10.5 (10.2) 0–38 | 6.5 (8.6) 0–36 | 4.0 (-0.3 to 8.4) | −0.01 |
4 months | 11.6 (9.9) 0–36 | 5.4 (7.3) 0–32 | 6.8* (2.5 to 11.0) | |
12 months | 10.4 (9.2) 0–32 | 5.5 (8.9) 0–40 | 5.6* (1.1 to 9.9) | |
DASS – anxiety | ||||
Baseline | 8.4 (9.2) 0–40 | 6.1 (7.3) 0–32 | 2.4 (-1.5 to 6.2) | |
Post-treatment | 8.2 (7.7) 0–32 | 5.9 (7.4) 0–32 | 2.3 (-1.1 to 5.8) | 0.11 |
4 months | 9.2 (7.4) 0–30 | 4.0 (5.2) 0–22 | 5.5* (2.3 to 8.6) | |
12 months | 6.1 (5.4) 0–20 | 4.0 (5.1) 0–16 | 2.2 (-0.4 to 4.8) | |
DASS – stress | ||||
Baseline | 14.7 (9.1) 2–42 | 12.1 (7.3) 0–32 | 2.7 (-1.1 to 6.5) | |
Post-treatment | 16.7 (10.3) 0–42 | 10.6 (8.3) 0–34 | 6.1* (1.8 to 10.5) | 0.38 |
4 months | 16.6 (11.1) 0–38 | 8.9 (7.8) 0–30 | 7.7* (3.2 to 12.2) | |
12 months | 13.1 (7.4) 0–28 | 7.2 (6.1) 0–20 | 5.9* (−9.2 to –2.5) | |
Healthcare use† | ||||
GP visits | ||||
Baseline | 1.16 (1.6) 0–8 | 0.73 (1.0) 0–4 | – | – |
4 months | 1.08 (1.2) 0–3 | 0.46 (0.8) 0–3 | – | – |
12 months | 1.39 (1.6) 0–7 | 0.77 (1.3) 0–4 | – | – |
Physiotherapy visits Mean (SD) | ||||
Baseline | 0.84 (1.4) 0–5 | 0.89 (1.7) 0–6 | – | – |
4 months | 0.44 (0.8) 0–3 | 0.37 (1.2) 0–6 | – | – |
12 months | 0.44 (1.1) 0–5 | 0.1 (0.4) 0–2 | – | – |
Level of use of prescribed medication, mean (SD) | ||||
Baseline | 0.71 (0.5) 0–1 | 0.49 (0.5) 0–1 | – | – |
4 months | 0.6 (0.5) 0–1 | 0.26 (0.4) 0–1 | – | – |
12 months | 0.58 (0.5) 0–1 | 0.3 (0.5) 0–1 | – | – |
Mean effect size for between group differences from baseline to post-treatment. Healthcare use at baseline, 4 months and 12 months.
*P<0.05.
†Measures taken at baseline, 4 months and 12 months only; self-reported healthcare use for previous month.
DASS, Depression Anxiety Stress Scale; GP, general practitioner; NRS, numerical rating scale; PSEQ, Pain Self-Efficacy Questionnaire; QBPDS, Quebec Back Pain Disability Score; TSK, Tampa Scale for Kinesiophobia.