Assessing Causal Effects with Time-Varying Treatments and Outcomes

Instruction: Explain how to assess the causal effect of a time-varying treatment (e.g., varying levels of training intensity) on a time-varying outcome (e.g., monthly sales performance) using appropriate causal inference methodologies.

Context: This question challenges the candidate to discuss complex causal inference scenarios involving time-varying treatments and outcomes. The answer should include a discussion on the selection of appropriate models, dealing with time-varying confounding, and methods to ensure robust causal estimations.