Statistical analysis of continuous outcomes from parallel-arm randomized controlled trials in nutrition-a tutorial.

Area of Science:

• Nutrition Science
• Biostatistics
• Clinical Trials

Background:

• Randomized controlled trials (RCTs) are crucial for nutrition research.
• Limited literature exists on analyzing data from nutrition RCTs.
• Understanding trial design's impact on statistical analysis is key.

Purpose of the Study:

• To provide a detailed tutorial on the statistical analysis of parallel-arm RCTs in nutrition.
• To introduce modern statistical methodologies for nutrition trial data.
• To explain how trial design influences statistical analysis.

Main Methods:

• Focus on analysis of covariance (ANCOVA).
• Focus on linear mixed models (LMMs).
• Statistical methods are informed by specific trial design elements.

Main Results:

• Demonstrates how trial design impacts statistical analysis choices.
• Covers all essential steps for statistical analysis of nutrition RCTs.
• Includes a practical example for application.

Conclusions:

• Effective statistical analysis of nutrition RCTs requires considering trial design.
• Modern methods like ANCOVA and LMMs offer robust approaches.
• This tutorial equips researchers with practical skills for nutrition trial data analysis.