---
title: "Open-label trial"
chunk: 1/1
source: "https://en.wikipedia.org/wiki/Open-label_trial"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T03:44:27.552355+00:00"
instance: "kb-cron"
---

An open-label trial, or open trial, is a type of clinical trial in which information is not withheld from trial participants. In particular, both the researchers and participants know which treatment is being administered. This contrasts with a double-blinded trial, where information is withheld both from the researchers and the participants to reduce bias.
Open-label trials may be appropriate for comparing two similar treatments to determine which is most effective, such as a comparison of different prescription anticoagulants, or possible relief from symptoms of some disorders when a placebo is given.
An open-label trial may still be randomized. Open-label trials may also be uncontrolled (without a placebo group), with all participants receiving the same treatment. This would be a single-arm study design.


== References ==