Confounding is the primary threat to validity in observational comparative effectiveness research (CER).
Multiple statistical methods have been adopted to address measured, unmeasured, and time-varying confounders.
Sensitivity analyses are essential to evaluate the robustness of findings in the presence of confounders.
Writing guidelines and reporting standards are fundamental to ensure transparency and reproducibility.
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| Wang Y., Li W., Wang L., et al. (2026). Addressing confounders in observational comparative effectiveness research: Methods, software, and reporting standards. The Innovation Medicine 4:100187. https://doi.org/10.59717/j.xinn-med.2026.100187 |
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Causal diagram (DAG) of confounders
Causal diagram (DAG) of instrumental variables (IVs)
Causal diagram (DAG) of IV, CIV and AIV
Diagram of difference-in-differences (DID)
Causal diagram (DAG) of NCEs and NCOs
Causal diagram (DAG) of confounding structure