So sánh phương pháp

	Nghiên cứu giai đoạn IV có điều chỉnh rủi ro	Nghiên cứu thuần tập
Lĩnh vực	Dịch tễ học	Dịch tễ học
Họ	Process / pipeline	Process / pipeline
Năm ra đời	1990s–2000s (formalized with ICH E2E and EMA PASS guidelines)	Mid-20th century (formal epidemiological design codified ~1950s)
Người khởi xướng	Regulatory and pharmacoepidemiology community (ICH, EMA, FDA frameworks)	Doll & Hill (British Doctors Study, 1951); Snow (cholera, 1854)
Loại	Observational / quasi-experimental clinical study design	Observational longitudinal study design
Công trình gốc	Strom, B. L. (Ed.). (2005). Pharmacoepidemiology (4th ed.). John Wiley & Sons. ISBN: 978-0470863107	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641
Tên gọi khác	risk-adjusted post-marketing surveillance study, adjusted Phase IV trial, risk-stratified post-authorization study, PASS with risk adjustment	longitudinal study, follow-up study, panel study, incidence study
Liên quan	3	6
Tóm tắt	A risk-adjusted Phase IV study is an observational or semi-experimental post-marketing study conducted after a drug or device has received regulatory approval. It uses statistical risk-adjustment techniques — such as propensity score matching, inverse probability weighting, or multivariable regression — to control for confounding by indication and baseline patient differences, thereby producing more credible safety, effectiveness, and utilization estimates than unadjusted real-world analyses.	A cohort study assembles a group of individuals who share a common starting point — typically freedom from the outcome of interest — and follows them over time to observe who develops the outcome. By comparing incidence rates between exposed and unexposed subgroups, researchers can estimate relative risk and absolute risk differences. Cohort studies are the gold-standard observational design for measuring disease incidence and establishing temporal relationships between exposure and outcome.