From: How do you design randomised trials for smaller populations? A framework
Scenario | Number to recruit | Events required | Time for: |
---|---|---|---|
 | (change vs. row 2) | (change vs. row 2) | recruitment – follow-up |
(Actual) | 576 | 147 | 3.5 years – 5 years |
Increase target HR to 0.7 | 929 (0) | 250 (0) | 3.5 years – 5.0 years |
Extend follow-up by 6 months | 820 (–109) | 250 (0) | 3.5 years – 5.5 years |
Move to one-sided tests | 646 (–283) | 197 (–53) | 3.5 years – 5.5 years |
Relax alpha to: | Â | Â | Â |
6 % | 600 (–329) | 183 (–67) | 3.5 years – 5.5 years |
7 % | 561 (–368) | 171 (–79) | 3.5 years – 5.5 years |
8 % | 527 (–402) | 161 (–89) | 3.5 years – 5.5 years |