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Causal inference for recurrent events via aggregated marginal odds ratio
Wenling Zhang1, Cecilia A Cotton1
1Department of Statistics and Actuarial Science, University of Waterloo, Waterloo, Ontario, Canada.
Statistics in Medicine
|June 9, 2023
Summary
This study introduces a new method to measure the causal effect of time-varying treatments on recurrent events, crucial for understanding therapies like cognitive behavior therapy for depression.
Area of Science:
- Epidemiology
- Biostatistics
- Psychology
Background:
- Causal effect measures are underdeveloped for time-varying treatments and recurrent events.
- Recurrent events and time-varying treatments are common in psychological and medical research.
- Existing measures are primarily designed for single, one-time treatments.
Purpose of the Study:
- To propose a novel causal measure for quantifying the impact of time-varying treatments on recurrent events.
- To develop robust estimators with standard errors for various weight models.
- To compare the performance of different weight models in estimating causal effects.
Main Methods:
- Development of a new causal estimand for time-varying treatments and recurrent events.
- Utilizing inverse probability weight models, including stabilized versions, for estimation.
- Comparison of estimation results across different treatment settings and weight models.
- Demonstration of consistent estimation for moderately long study periods.
Main Results:
- The proposed causal estimand can be consistently estimated.
- Stabilized inverse probability weight models show advantages in certain settings.
- The method is effective for both absorbing and nonabsorbing treatments.
- The approach was successfully applied to the 1997 National Longitudinal Study of Youth.
Conclusions:
- The novel causal measure effectively quantifies the effect of time-varying treatments on recurrent events.
- The proposed estimation methods provide robust standard errors and are suitable for various weight models.
- The approach is applicable to diverse treatment scenarios, including those in psychological research.
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