1. Introduction | 2. Eliciting the Truncated Gamma Prior for DTE Separation Timepoint ( S ) | 3. Calculating Median Survival Times for Pre- and Post-Separation DTE Timepoint given DTE timepoint S | 4. Determination of Sample Size in a Two-Stage Design Setting | 5. Conduct the Trial: Make Go/No-Go Decision | 6. Summary | 7. Example 1 | 8. Incorporating Early Stopping Probability into Sample Size Determination | 9. Application of the Proposed Method in a Three-Stage Design | 10. When an expert-elicited prior with high certainty is used | Conclusion | References