986 / 1674
Statistical considerations
47
Sample size
•
Non-inferiority design
•
Assumed 2.5% LR rate at 5 years in control group
•
Exclude >2.5% increase in LR rate in either test group
•
80% power
•
2.5% α, 1-sided for each comparison of test group versus
control
•
645 required in each group (1935 total)
Data maturity
•
Primary efficacy analysis after median follow-up of at
least 5 years
•
Long term follow-up for at least 10 years