what is Per-Protocol Analysis

In conclusion, ITT analysis is generally recommended as the primary method for reporting trial results because it reflects the true effectiveness of a treatment in real-world settings, where protocol deviations are common. PP analysis, on the other hand, should be used cautiously, as it can introduce bias by excluding participants who did not adhere to the protocol. Both methods have their strengths and limitations, and researchers should clearly explain their choice of analysis method and its implications for the interpretation of trial results. 1. **ITV Analysis**: - ITT analysis includes all patients who were randomized, regardless of protocol adherence, to provide an estimate of treatment effect in a realistic-world setting. - It is considered the gold standard for reporting clinical trial results because it avoids bias associated with excluding participants who did not adhere to the protocol. - ITT analysis is particularly important in trials where adherence to the protocol is expected to be low, as it provides a more accurate representation of how the treatment will be used in practice. 2. **PP Analysis**: - PP analysis considers only those patients who completed the treatment as intended, excluding those with protocol deviations. - This approach can provide a more accurate estimate of treatment effect when adherence to the protocol is high and the treatment is intended to be taken over a specific period. - However, PP analysis can be biased if protocol deviations are not evenly distributed between treatment groups, leading to inaccurate comparisons. 3. **Key Considerations**: - Both ITT and PP analyses have their place in different types of trials. In superiority trials, ITT analysis is recommended to avoid bias, while in noninferiority trials, both ITT and PP analyses may be necessary to support the trial’s objectives. - Researchers should clearly state the analysis method used and justify the choice based on the trial’s design and objectives. 4. **Real-World Implications**: - In real-world settings, patients may not always adhere to their treatment protocols, which can impact the effectiveness of the treatment. ITT analysis provides a more conservative estimate of treatment effect, taking into account these real-world complexities. - PP analysis, on the other hand, can provide a more optimistic view of treatment effectiveness when adherence is high, but may not reflect how the treatment will perform in real-world settings where adherence may be lower. By understanding the differences between ITT and PP analysis, researchers and clinicians can make more informed decisions about the interpretation of trial results and their applicability to real-world settings.