방법 비교

	다기관 증례 시리즈	후향적 증례 시리즈
분야	역학	역학
계열	Process / pipeline	Process / pipeline
기원 연도	Mid-to-late 20th century (collaborative multi-site reporting common by 1970s–1980s)	Long-standing practice; codified in EBM frameworks during 1990s–2000s
창시자	Evolved from single-center case series practice; formalized in 20th century clinical reporting	Clinical medicine tradition (no single originator); formalized in evidence-based medicine literature
유형	Observational descriptive study	Observational descriptive study design
원전	Dekkers, O. M., Vandenbroucke, J. P., Cevallos, M., Renehan, A. G., Altman, D. G., & Egger, M. (2012). COSMOS-E: Guidance on conducting systematic reviews and meta-analyses of observational studies of etiology and prognosis. PLoS Medicine, 9(2), e1001175.	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.
별칭	multi-site case series, multicentre case series, collaborative case series, multi-institutional case series	retrospective case series, chart review case series, historical case series, medical records case series
관련	5	4
요약	A multicenter case series is an observational descriptive study in which consecutive or selected patients sharing a defined clinical condition are enrolled and followed at two or more independent clinical sites. By pooling cases across institutions, researchers achieve larger sample sizes and greater demographic and clinical diversity than a single-center series permits, enabling more reliable description of disease presentation, management patterns, and outcomes for rare or uncommon conditions.	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.