手法を比較

	実薬フェーズIV試験	コホート研究
分野	疫学	疫学
系統	Process / pipeline	Process / pipeline
提唱年	1967 (pragmatic concept); 2000s (pragmatic Phase IV formalized)	Mid-20th century (formal epidemiological design codified ~1950s)
提唱者	Schwartz & Lellouch (explanatory vs. pragmatic distinction, 1967); PRECIS framework by Thorpe et al. (2009)	Doll & Hill (British Doctors Study, 1951); Snow (cholera, 1854)
種類	Observational / interventional hybrid study design	Observational longitudinal study design
原典	Thorpe, K. E., Zwarenstein, M., Oxman, A. D., Treweek, S., Furberg, C. D., Altman, D. G., ... & Chalkidou, K. (2009). A pragmatic-explanatory continuum indicator summary (PRECIS): a tool to help trial designers. Journal of Clinical Epidemiology, 62(5), 464-475.	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641
別名	pragmatic post-marketing study, real-world phase IV trial, pragmatic pharmacovigilance study, pragmatic post-approval study	longitudinal study, follow-up study, panel study, incidence study
関連	5	6
概要	A pragmatic Phase IV study is a post-marketing investigation conducted under routine clinical conditions to evaluate a drug or device's real-world effectiveness, long-term safety, and comparative performance. Unlike the controlled Phase III environment, it intentionally minimizes protocol restrictions — broad eligibility criteria, standard-of-care comparators, and naturalistic follow-up — to generate evidence directly applicable to everyday clinical practice.	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.