手法を比較

	前向き第IV相試験	コホート研究
分野	疫学	疫学
系統	Process / pipeline	Process / pipeline
提唱年	1970s–1980s (formalized in post-marketing regulatory frameworks)	Mid-20th century (formal epidemiological design codified ~1950s)
提唱者	Regulatory and pharmaceutical research community (ICH E2E, EMA PASS guidelines)	Doll & Hill (British Doctors Study, 1951); Snow (cholera, 1854)
種類	Observational / interventional post-marketing study design	Observational longitudinal study design
原典	Strom, B.L. (Ed.). (2005). Pharmacoepidemiology (4th ed.). Wiley. ISBN: 978-0470863088	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641
別名	prospective post-marketing surveillance study, prospective pharmacovigilance study, prospective post-authorization safety study, PASS (prospective)	longitudinal study, follow-up study, panel study, incidence study
関連	5	6
概要	A prospective Phase IV study is a post-marketing investigation conducted after a drug, device, or intervention has received regulatory approval, following participants forward in real time to collect safety, effectiveness, and utilization data under routine clinical practice conditions. Unlike retrospective designs that mine existing records, prospective enrollment allows pre-specified data collection, defined follow-up windows, and direct measurement of outcomes as they occur, making it central to post-authorization safety surveillance and long-term effectiveness research.	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.