Table 3.

Sample sizes needed to detect the listed mean paired differences using two-sided Wilcoxon-Mann-Whitney test (two sample parallel group design) and paired Wilcoxon Signed-Rank test (crossover design) at a 2-sided significance level (α) of 0.05 and at 80% power.

	SF12v2 assessment		Total sample size required for a two-sample parallel group design to detect a mean difference of			Total sample size required for a one-sample crossover design to detect a mean difference of
	Mean score	SD	2	5	10	2	5	10
Type I collagen-related OI (Types I, III, and IV)
PCS	44.8	10.1	824	136	36	55	11	6
OI type I
PCS	46.4	10.6	926	152	40	55	11	6
OI Type III
PCS	39.9	7.1	418	70	20	36	9	5
OI type IV
PCS	44.3	9.5	744	122	34	44	10	5