手法を比較

	実用的ランダム化比較試験 ― 実臨床における有効性	コホート研究
分野	疫学	疫学
系統	Process / pipeline	Process / pipeline
提唱年	1967	Mid-20th century (formal epidemiological design codified ~1950s)
提唱者	Daniel Schwartz & Joseph Lellouch	Doll & Hill (British Doctors Study, 1951); Snow (cholera, 1854)
種類	Interventional study design	Observational longitudinal study design
原典	Schwartz, D., & Lellouch, J. (1967). Explanatory and pragmatic attitudes in therapeutical trials. Journal of Chronic Diseases, 20(8), 637–648.	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641
別名	pragmatic RCT, effectiveness trial, real-world RCT, practical clinical trial	longitudinal study, follow-up study, panel study, incidence study
関連	6	6
概要	A pragmatic randomized clinical trial (pragmatic RCT) is an interventional study that tests whether a treatment works under routine clinical conditions, as opposed to the tightly controlled setting of an explanatory trial. It prioritizes broad eligibility, flexible delivery, and patient-relevant outcomes to answer the question 'Does this treatment work in everyday practice?' rather than 'Can this treatment work under ideal circumstances?' The distinction between pragmatic and explanatory trials was formally articulated by Schwartz and Lellouch in 1967 and operationalized by the PRECIS tool in 2009.	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.