手法を比較

	後ろ向きケースシリーズ	後向き症例対照研究
分野	疫学	疫学
系統	Process / pipeline	Process / pipeline
提唱年	Long-standing practice; codified in EBM frameworks during 1990s–2000s	1950s–1960s (formal methodology)
提唱者	Clinical medicine tradition (no single originator); formalized in evidence-based medicine literature	Jerome Cornfield; formalized by Brian MacMahon and others in mid-20th-century epidemiology
種類	Observational descriptive study design	Observational analytical study
原典	Kooistra, B., Dijkman, B., Einhorn, T. A., & Bhandari, M. (2009). How to design a good case series. Journal of Bone and Joint Surgery, 91(Suppl 3), 21–26.	Schlesselman, J. J. (1982). Case-Control Studies: Design, Conduct, Analysis. Oxford University Press. ISBN: 978-0195029338
別名	retrospective case series, chart review case series, historical case series, medical records case series	case-control study, retrospective case-referent study, case-referent design, trohoc study
関連	4	5
概要	A retrospective case series is an observational study that systematically describes the clinical features, treatments, and outcomes of a defined group of patients by examining pre-existing medical records or administrative data. It looks backward in time — data have already been recorded before the study begins. With no control group, no randomization, and no prospective follow-up, it sits near the base of the evidence hierarchy but remains one of the most practical and frequently published study designs in clinical medicine.	A retrospective case-control study identifies individuals who already have an outcome of interest (cases) and a comparable group without it (controls), then looks backward in time using existing records to determine prior exposure to a suspected risk factor. The primary measure of association is the odds ratio. This design is especially efficient for studying rare diseases or outcomes with long latency periods, since the outcome has already occurred before the study begins.