Table 1 Main characteristics of conventional two-arm and alternative multi-arm duration trial designs
From: Optimising trial designs to identify appropriate antibiotic treatment durations
| Â | Two-arm duration design | Bayesian multi-arm, response-adaptive randomisation design | Multi-arm, play-the-winner design | Multi-arm, fixed duration design | Multi-arm, drop-the-loser duration design |
|---|---|---|---|---|---|
Obtain information on treatment durations | Only two considered durations | Can model the entire duration–response curve, including estimates for durations that were not used | Can model the entire duration–response curve, including estimates for durations that were not used | Can model the entire duration–response curve, including estimates for durations that were not used | Can model the entire duration–response curve, including estimates for durations that were not used |
Randomisation probabilities | Fixed | Variable and possibility to drop arms | Fixed, but with possibility to select shortest duration with high probability of being non-inferior for comparison with standard duration | Fixed | Fixed, but with possibility to drop arms |
Higher chance for patients to be randomised to better-performing treatment arm | No | Yes | Yes | No | No, but poor performing arms can be dropped |