[Roaming through methodology. III. Randomization at the level of the physicians]

Area of Science:

• Medical Statistics
• Clinical Trial Design

Background:

• Patient-level randomization is not always feasible in clinical studies.
• Doctor-level randomization presents unique statistical analysis challenges.

Purpose of the Study:

• To address the statistical complexities of doctor-level randomization.
• To ensure accurate significance testing and sample size determination in such designs.

Main Methods:

• Analyzing data based on doctor-level averages to maintain correct significance levels.
• Utilizing a correction factor for sample size calculations, considering between-doctor variation.
• Employing advanced statistical techniques like mixed models to account for doctor-level effects.

Main Results:

• Analysis of doctor-level averages provides a statistically valid approach.
• Correction factors enable accurate sample size determination.
• Mixed models offer a sophisticated method for handling doctor-level variation.

Conclusions:

• Doctor-level randomization necessitates specific statistical approaches for valid interpretation.
• Averaging data per doctor and using mixed models are key to reliable analysis.
• Proper statistical methods ensure the integrity of findings in doctor-randomized studies.