手法を比較

	リスク調整済み症例シリーズ	症例集
分野	疫学	疫学
系統	Process / pipeline	Process / pipeline
提唱年	1990s–2000s	Longstanding; systematized in 20th century clinical research
提唱者	Copeland, Jones & Walters (POSSUM score, 1991); broader risk-adjustment methodology developed across surgical and critical care audit literature	Historical clinical practice; formalized in modern evidence-based medicine literature
種類	Observational study design with statistical risk correction	Observational descriptive study
原典	Copeland, G. P., Jones, D., & Walters, M. (1991). POSSUM: a scoring system for surgical audit. British Journal of Surgery, 78(3), 355–360.	Case series. Wikipedia.
別名	risk-stratified case series, adjusted case series, risk-corrected case series	case series report, clinical case series, consecutive case series, patient series
関連	5	5
概要	A risk-adjusted case series is an observational study design that reports outcomes for a consecutive or defined group of patients undergoing the same procedure or sharing a condition, while statistically correcting for differences in patient-level baseline risk. Rather than presenting raw complication or mortality rates, it compares observed outcomes against expected rates derived from a validated scoring model (e.g., POSSUM, APACHE, ASA grade), enabling fairer evaluation of clinical performance across institutions or over time.	A case series is a descriptive observational study that documents the characteristics, clinical course, and outcomes of a group of patients who share a common condition, exposure, or intervention. Unlike case reports, which focus on a single patient, a case series aggregates data across multiple patients (typically three or more) to identify patterns, generate hypotheses, and characterize rare or novel conditions — without a concurrent control group.