Table 1.

Iterations of mean difference and standard deviations (SD). Estimates in cells are the calculated power given equal sample sizes in control and intervention group and common SD

Power/ %		Mean difference/points
SD/points	1.5	2	2.5	3	3.5
1.5	96	100	100	100	100
2	79	96	100	100	100
2.5	60	84	96	100	100
3	45	69	86	96	100
3.5	35	56	75	88	96

Iterations are based on a sample size of 56 patients allowing for a loss to follow-up of 20%. The power calculation closest to the feasibility study’s estimate of effect is marked in its cell in bold

Note: effect size iterating from 1.5 points to 3.5 points in 4 steps of 0.5 points. The standard deviation is iterated from 1.5 points to 3.5 points in 4 steps of 0.5 points