# 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
1. *: p < 0.01
2. **: the 99 % confidence interval for the absolute risk reduction extends from a negative number to a positive number, and a 99 % CI for the NNT cannot be computed
3. +: NNT calculated from unadjusted treatment success values