{"entity":{"id":"intention-to-treat","kind":"term","name":"Intention-to-treat (ITT) and per-protocol analysis","aka":["ITT","intention-to-treat","intent-to-treat","ITT population","ITT analysis","modified intention-to-treat","mITT","per-protocol","per protocol","per-protocol population","as-treated","evaluable population","efficacy-evaluable","response-evaluable","safety population","full analysis set","analysis population","randomised population"],"tldr":"Analysing every patient in the group they were randomised to, whether or not they actually took the treatment. It preserves the fairness of randomisation and reflects what happens when a treatment is prescribed in real life; per-protocol analysis, by contrast, counts only those who complied.","summary":"ITT is the primary analysis for superiority trials because excluding non-compliers or early dropouts reintroduces bias. Per-protocol analyses matter for non-inferiority trials, where non-compliance can mask a real difference. 'Modified ITT' variants exclude patients who never received a dose or lacked a baseline measurement and should be pre-specified. 'Response-evaluable' populations in single-arm trials inflate response rates by dropping early progressors, and 'safety population' counts patients as treated. Trial and drug pages on this site report ITT results unless stated.","asOf":"2026-09-09","wikipedia":"https://en.wikipedia.org/wiki/Intention-to-treat_analysis","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Intention-to-treat_analysis"}],"tags":[],"related":["non-inferiority","prespecified-vs-post-hoc","double-blind","control-arm","estimand","non-inferiority-margin","trial-failure-modes","randomised-trial"],"cancers":[],"sections":["drug-discovery"],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":["persephone","tailorx"],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"category":"Trials"},"route":"/terms/intention-to-treat/","neighbours":{"term":[{"id":"double-blind","kind":"term","name":"Blinding (double-blind, open-label, placebo-controlled)","route":"/terms/double-blind/"},{"id":"control-arm","kind":"term","name":"Control arm and comparator (investigator's choice)","route":"/terms/control-arm/"},{"id":"estimand","kind":"term","name":"Estimands and intercurrent events (ICH E9(R1))","route":"/terms/estimand/"},{"id":"non-inferiority-margin","kind":"term","name":"Non-inferiority margin and equivalence trials","route":"/terms/non-inferiority-margin/"},{"id":"non-inferiority","kind":"term","name":"Non-inferiority trial","route":"/terms/non-inferiority/"},{"id":"prespecified-vs-post-hoc","kind":"term","name":"Pre-specified vs post-hoc analysis","route":"/terms/prespecified-vs-post-hoc/"},{"id":"randomised-trial","kind":"term","name":"Randomised trial","route":"/terms/randomised-trial/"},{"id":"trial-failure-modes","kind":"term","name":"Why trials fail: underpowered, wrong endpoint, control arm drift, subgroup fishing, crossover","route":"/terms/trial-failure-modes/"}],"section":[{"id":"drug-discovery","kind":"section","name":"Drug Discovery Platforms","route":"/fronts/drug-discovery/"}],"trial":[{"id":"persephone","kind":"trial","name":"PERSEPHONE","route":"/trials/persephone/"},{"id":"tailorx","kind":"trial","name":"TAILORx","route":"/trials/tailorx/"}]}}