Table 1.

Samples sizes required for PROTECTS to have 80% power to detect an effect of 0.25 in patients who consent to treatment, under both cmRCT and pRCT designs

Percentage of patients consenting to trial	cmRCT				pRCT
	Effect size to be detected (adjusted for consent rate)	Patients selected	Patients consented	Patients in treatment vs. control arms	Effect size to be detected	Patients invited	Patients consented	Patients in treatment vs. control arms
100%	0.25	139	139	139 vs. 1167	0.25	504	504	252 vs. 252
90%	0.225	178	160	178 vs. 1128	0.25	560	504	252 vs. 252
80%	0.2	237	190	237 vs. 1069	0.25	630	504	252 vs. 252
70%	0.175	344	241	344 vs. 962	0.25	720	504	252 vs. 252
62%	0.155	653	405	653 vs. 653	0.25	813	504	252 vs. 252
60%	<80% power				0.25	840	504	252 vs. 252
50%	<80% power				0.25	1008	504	252 vs. 252
40%	<80% power				0.25	1260	504	252 vs. 252

Abbreviations: cmRCT, cohort multiple randomized controlled trial; pRCT, pragmatic RCT.