Outcome measured by an assessor unaware of which treatment the participant received.
Blinded outcome assessment means the person measuring or judging a study outcome (e.g. scoring a scan, rating pain, assessing return-to-sport readiness) does not know which arm (treatment vs control) the participant was allocated to. This reduces detection/ascertainment bias, particularly important for subjective or judgement-based outcomes; it matters less for fully objective, automated measures. It is distinct from participant or therapist blinding, and a study can have one without the others.
This guide was auto-drafted and is pending editorial review.