방법 비교

	위험 조정된 4상 연구	코호트 연구
분야	역학	역학
계열	Process / pipeline	Process / pipeline
기원 연도	1990s–2000s (formalized with ICH E2E and EMA PASS guidelines)	Mid-20th century (formal epidemiological design codified ~1950s)
창시자	Regulatory and pharmacoepidemiology community (ICH, EMA, FDA frameworks)	Doll & Hill (British Doctors Study, 1951); Snow (cholera, 1854)
유형	Observational / quasi-experimental clinical study design	Observational longitudinal study design
원전	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
별칭	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
관련	3	6
요약	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.