Rationale for the selection of dual primary endpoints in prevention studies of cognitively unimpaired individuals at genetic risk for developing symptoms of Alzheimer’s disease

Table 5 Power of clinical trial replicates (1000 simulation runs) for the 1:2:2 age distribution

HR	Power given the distribution (%) of type 1 error rate for TTE/APCC
HR	100%/0% single primary endpoint: TTE	80%/20%	50%/50%	20%/80%	0%/100% single primary endpoint: APCC
0.60	0.959	0.952	0.943	0.914	0.798
0.65	0.877	0.855	0.822	0.777	0.653
0.67	0.840	0.819	0.785	0.735	0.581
0.70	0.752	0.723	0.693	0.645	0.525
0.75	0.581	0.556	0.499	0.439	0.337

APCC Alzheimer’s Prevention Initiative Preclinical Composite Cognitive, HR hazard ratio, TTE time to event

ISSN: 1758-9193