Table 2 Treatment success. Unadjusted event rates of treatment success, defined as participants rating themselves much improved or completely recovered on a six point scale; estimated odds ratio for success between groups using logistic generalized estimating equations (GEE) regression model adjusted for significant covariates with numbers needed to treat (NNT); estimated odds ratio for success within each group compared to week 6 using logistic GEE regression model adjusted for significant covariates; 99 % confidence intervals. NNT calculated from unadjusted treatment success values
Unadjusted percentage of treatment success (99 % CI) at each follow up | |||||||||
|---|---|---|---|---|---|---|---|---|---|
Control | Placebo injection with physiotherapy | Corticosteroid injection (CI) with physiotherapy | |||||||
Follow up | (n = 60) | (n = 58) | (n = 59) | ||||||
weeks | % (99 % CI) | % (99 % CI) | % (99 % CI) | ||||||
6 | 15 (3 to27) | 24 (10 to 39) | 59 (43–76) | ||||||
12 | 48 (32 to 65) | 45 (28 to 62) | 42 (26 to 59) | ||||||
26 | 67 (51 to 82) | 69 (53 to 85) | 42 (26 to 59) | ||||||
52 | 78 (65 to 92) | 78 (64 to 92) | 75 (60 to 89) | ||||||
Estimated Odds Ratio (99 % CI) and NNT + for treatment success between groups | |||||||||
Placebo injection with physiotherapy versus control | P | NNT (99 % CI) | CI with physiotherapy versus control | P | NNT (99 % CI) | CI with physiotherapy versus placebo injection with physiotherapy | P | NNT (99 % CI) | |
OR > 1 favours first treatment in comparison | |||||||||
6 | 3.37 (0.72 to 15.82) | 0.04 | 11 ** | 10.60 (2.20 to 51.24)* | <0.01 | 3 (1.5 to 4.2) | 3.14 (0.72 to 13.75) | 0.045 | 3 (1.8 to 7.5) |
12 | 0.18 (0.02 to 1.47) | 0.04 | 29 ** | 0.15 (0.02 to 1.24) | 0.02 | 17** | 0.81 (0.10 to 6.37) | 0.80 | 41 ** |
26 | 0.37 (0.04 to 3.35) | 0.25 | 44 ** | 0.09 (0.01 to 0.76)* | <0.01 | 5 (2.1 to 67.4) | 0.24 (0.03 to 2.05) | 0.09 | 4 (2.0 to 26.3) |
52 | 0.12 (0.01 to 1.50) | 0.03 | 134 ** | 0.17 (0.01 to 2.63) | 0.10 | 27 ** | 1.49 (0.13 to 17.12) | 0.67 | 34 ** |
Estimated Odds Ratio (99 % CI) for treatment success compared to week 6 within each group | |||||||||
Control | P | Placebo injection with physiotherapy | P | CI with physiotherapy | P | ||||
OR > 1 indicates improvement compared to week 6 | |||||||||
12 | 7.17 (1.53 to 33.66)* | <0.01 | 1.30 (0.32 to 5.26) | 0.63 | 1.05 (0.23 to 4.75) | 0.93 | |||
26 | 6.09 (1.27 to 29.29)* | <0.01 | 2.25 (0.47 to 10.81) | 0.18 | 0.55 (0.13 to 2.39) | 0.29 | |||
52 | 14.84 (1.92 to 114.57)* | <0.01 | 1.70 (0.34 to 8.43) | 0.39 | 2.54 (0.40 to 16.01) | 0.19 | |||