{"entity":{"id":"censoring-and-events","kind":"term","name":"Censoring and events in survival data","aka":["right-censored","censored patients","censored observations","event count","number of events","events observed"],"tldr":"A patient is censored when the study ends or they leave before the event (death or progression) happens, so we only know they survived at least that long.","summary":"Censoring, in Wikipedia's definition, is when the value of an observation is only partly known; in survival analysis a right-censored patient has not had the event by the last follow-up. Survival methods (Kaplan-Meier, Cox regression, the concordance index) use censored patients up to their last known time. The number of events, not the number of patients, sets the statistical power of a survival model, which is why a cohort of two thousand with a hundred deaths is a small study.","asOf":"2026-09-24","wikipedia":"https://en.wikipedia.org/wiki/Censoring_(statistics)","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Censoring_(statistics)"}],"tags":["cansim-terms"],"related":["cancer-ai-vocabulary"],"cancers":[],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["kaplan-meier-curve","hazard-ratio","concordance-index"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":["Listed in the CanSim terms map 1.0.0 (docs/onco/terms.json, generated 2026-09-24), CC BY 4.0, attribution: CanSim project, an open, public-data-first cancer foundation-model programme; CanSim page path /terms/censoring-events."],"provenance":{"editedBy":"OnCo CanSim terms wave (Wikipedia summaries, standards and project pages, GDC and FDA pages, Europe PMC)","editedOn":"2026-09-24","note":"CanSim terms map 1.0.0 (docs/onco/terms.json, generated 2026-09-24), CC BY 4.0, attribution: CanSim project, an open, public-data-first cancer foundation-model programme"},"category":"Endpoints"},"route":"/terms/censoring-and-events/","neighbours":{"term":[{"id":"concordance-index","kind":"term","name":"C-index (concordance index), Harrell's and Uno's","route":"/terms/concordance-index/"},{"id":"cancer-ai-vocabulary","kind":"term","name":"Cancer AI vocabulary (CanSim terms map)","route":"/terms/cancer-ai-vocabulary/"},{"id":"hazard-ratio","kind":"term","name":"Hazard ratio (HR)","route":"/terms/hazard-ratio/"},{"id":"kaplan-meier-curve","kind":"term","name":"Kaplan-Meier curve, censoring and proportional hazards","route":"/terms/kaplan-meier-curve/"},{"id":"os-pfs-time-event","kind":"term","name":"Survival outcomes as time plus event (OS, PFS)","route":"/terms/os-pfs-time-event/"},{"id":"time-dependent-auc","kind":"term","name":"Univariate Cox scores and time-dependent metrics","route":"/terms/time-dependent-auc/"}]}}