External Control ArmRegistry Control Group, Synthetic Control Arm
A comparator group built from data outside the trial itself, such as a historical cohort or registry, used when no concurrent control is feasible.
Clinical Trials & Real-World Evidence
Terms for clinical trial design and for evidence drawn from routine practice outside trials.
- Topic: Clinical Trials & Real-World Evidence
- 40 terms
- Editor reviewed
Intention-to-Treat AnalysisITT Analysis, Intention to Treat
Intention-to-treat analysis compares outcomes according to participants’ original randomised assignments, irrespective of subsequent treatment receipt or adherence, while explicitly addressing missing outcome data.
Interim AnalysisInterim Look, Mid-Trial Analysis
A planned analysis of trial data conducted before final completion, typically to assess safety, efficacy, or futility and inform continuation decisions.
Loss to Follow-UpLTFU, Uncontactable Participant
A situation in which a study participant can no longer be reached before planned completion, resulting in incomplete outcome data.
Non-Inferiority TrialNI Trial, Non-Inferiority Study
A trial designed to show a new treatment is not meaningfully worse than an active comparator, within a predefined acceptable margin.
Observational StudyNon-Interventional Study, Observational Research
A study that observes exposures and outcomes without investigator assignment of the exposure under investigation, using a specified design to describe patterns or assess associations and, under additional assumptions, causal effects.
Open Label StudyOpen-Label Trial, Unblinded Study
A trial design in which both participants and researchers know which treatment each person is receiving, without any blinding of assignment.
Per-Protocol AnalysisPP Analysis, On-Treatment Analysis
An analysis including only trial participants who received and adhered to their assigned treatment as specified, excluding those with major protocol deviations.