Per-Protocol Analysis

Per-Protocol Analysis refers to a method of analyzing data from a clinical trial based only on participants who adhered to the protocol of the study. This means that only those individuals who completed the study according to the predetermined guidelines and treatment assignments are included in the analysis, potentially excluding those who dropped out, switched treatments, or deviated from the specified procedures.

For instance, in a clinical trial testing a new drug for hypertension, if a participant stops taking the medication or switches to another treatment, they would be excluded from the per-protocol analysis. This contrasts with an intent-to-treat analysis, where all participants are included regardless of adherence.

One common case for using per-protocol analysis is when assessing the efficacy of a treatment under ideal conditions. For example, if a study aims to determine how effective a weight loss program is among participants who strictly follow the diet and exercise plan, the per-protocol analysis would provide insights into the maximum potential benefits of the program.

However, it is essential to note that while per-protocol analysis can yield clearer results regarding the treatment effect, it may introduce bias, as it often excludes those who may not adhere to the protocol due to varying reasons, such as side effects or personal circumstances.