Comparison of visual analogue scale pain scores of group A (unaffected by potential carry-over effect) and group B (affected by potential carry-over effect)
VAS pain baseline | VAS pain placebo period | Placebo response (difference in VAS)* | ||||
Mean | SD (95% CI) | Mean | SD (95% CI) | Mean | SD(95% CI) | |
Group A (n=10) Unaffected by potential carry-over effect | 7.52 | 1.52 (6.43 to 8.60) | 6.55 | 1.54 (5.45 to 7.65) | −0.97 | 1.85 (−2.29 to 0.35) |
Group B (n=11) Affected by potential carry-over effect | 6.02 | 2.47 (4.36 to 7.68) | 4.55 | 1.82 (3.33 to 5.78) | −1.47 | 1.81 (−2.69 to 0.25) |
Mean | SD (95% CI) | |||||
Carry-over effect (difference in placebo response between group A and group B) | 0.50 | 1.83 (−1.17 to 2.17) |
*Difference in VAS pain between VAS pain baseline and VAS pain efficacy in placebo period.
VAS, visual analogue scale.