Evaluating analytic models for individually randomized group treatment trials with complex clustering in nested and crossed designs

  • 0Office of Disease Prevention, National Institutes of Health, Bethesda, Maryland, USA.

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Summary

This summary is machine-generated.

Individually Randomized Group Treatment (IRGT) trials require specific statistical models to account for shared treatment agents. Simulation results show that ignoring multiple membership in nested designs inflates errors, while crossed designs are more robust.

Area Of Science

  • Biostatistics
  • Clinical Trial Design
  • Epidemiology

Background

  • Individually Randomized Group Treatment (IRGT) trials randomize individuals but use shared agents for treatment delivery.
  • This shared agent results in post-randomization correlations among participants, complicating analysis.
  • Existing analytic models may not adequately address complex clustering in IRGT designs.

Purpose Of The Study

  • To evaluate the performance of statistical models for IRGT trials with complex clustering.
  • To identify appropriate analytic models for nested and crossed agent designs in IRGT studies.
  • To assess type I error rates under various clustering scenarios.

Main Methods

  • A simulation study was conducted to examine candidate analytic models.
  • Scenarios included single membership, multiple membership, and single agent settings.
  • Designs considered were both nested and crossed, with a continuous outcome.

Main Results

  • For nested designs, type I error rate inflation occurred when multiple membership was not accounted for or when model weights mismatched data generation.
  • Analytic models for crossed designs generally maintained nominal type I error rates.
  • Imbalance in participants per agent in crossed designs was a key factor affecting error rates.

Conclusions

  • Appropriate statistical modeling is crucial for accurate analysis of IRGT trials.
  • Nested designs require careful consideration of multiple membership to avoid inflated type I errors.
  • Crossed designs are more robust, but agent imbalance can still impact results.

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