Key Questions
1. What are Causal Forest Algorithms (CFAs)?
CFAs are machine learning methods used to estimate patient-specific treatment effects from observational data, accounting for heterogeneity in treatment responses.
2. What is essential heterogeneity, and how does it affect CFAs?
Essential heterogeneity occurs when unmeasured patient factors influencing treatment effects also affect treatment choice. Under this condition, CFAs may produce biased estimates, particularly for untreated patients.
3. How well did CFA-GRF perform in the study?
CFA-GRF performed well when treatment effect heterogeneity did not influence treatment choice but overestimated effects for untreated patients under essential heterogeneity.
4. What recommendations were made for researchers using CFAs?
Researchers should develop conceptual frameworks of treatment choice before estimation to guide the interpretation of CFA results, especially in real-world settings.