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Sample size calculations for micro-randomized trials in mHealth.
Peng Liao1, Predrag Klasnja2, Ambuj Tewari1
1Department of Statistics, University of Michigan, MI, 48109, Ann Arbor, U.S.A.
Statistics in Medicine
|December 29, 2015
Summary
This study introduces micro-randomized trials to evaluate mobile health interventions. This design helps assess the immediate impact of "just-in-time" treatments on behavior change.
Area of Science:
- Digital Health
- Behavioral Science
- Clinical Trials
Background:
- Mobile interventions are rapidly evolving, offering
Purpose of the Study:
- To propose a micro-randomized trial design for evaluating the proximal effects of just-in-time mobile interventions.
- To develop statistical methods and tools for analyzing data from such trials.
Main Methods:
- Introduced a micro-randomized trial design where participants are randomized multiple times.
- Developed a test statistic for assessing proximal treatment effects.
- Created a sample size calculator and conducted simulation studies.
Main Results:
- The proposed micro-randomized trial design and associated statistical methods provide a framework for testing proximal intervention effects.
- Simulation evaluations support the utility of the sample size calculator.
Conclusions:
- Micro-randomized trials are a suitable experimental design for assessing the immediate impact of mobile health interventions.
- The developed methods and tools can aid in the design and analysis of future mobile intervention studies, such as the HeartSteps application for physical activity.
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