Power calculations
pain
In the power calculations for a future RCT, we assumed that the patients would have similar baseline levels and SDs for pain intensity (primary health outcome) as in the present study. Furthermore, we assumed that the control group would also improve. Two different scenarios were used for the power calculations, with a statistical power of 0.80 and alpha of 0.05:In the first scenario, we approximated the mean difference in pain intensity between groups (study group and control group) to 1 and the SD to 2, resulting in 64 patients per group.For postoperative patients, we approximated the mean difference in pain intensity to 1.5 and the SD to 1.8, resulting in 24 patients per group.In the second scenario, we assumed that the pain intensity in a waiting list control group would decrease by 13%, as was observed in a somewhat similar study [For postoperative patients, we estimated the mean difference in pain intensity to 1.13 and the SD to 1.8, resulting in 41 patients per group.There will still be dropouts in an RCT, and given the same dropout frequency as in the present study (Fig. 