Despite its benefits, CER faces several challenges:
1. Heterogeneity of Data: Variability in data sources and patient populations can complicate the analysis and interpretation of results. 2. Bias: Observational studies can be prone to selection bias and confounding, which can affect the validity of the findings. 3. Ethical Concerns: Conducting RCTs for CER can raise ethical issues, especially if withholding a potentially beneficial treatment from a control group.
