Open-label trial explained

An open-label trial, or open trial, is a type of clinical trial in which information is not withheld from trial participants.^[1] In particular, both the researchers and participants know which treatment is being administered.^[1] This contrasts with a double-blinded trial, where information is withheld both from the researchers and the participants to reduce bias.^{[2] [3]}

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,^[4] or possible relief from symptoms of some disorders when a placebo is given.^[5]

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.^[4]

Notes and References

1. Web site: Open label study. National Cancer Institute, US National Institutes of Health. 2020. 20 November 2020.
2. Web site: Double-blind (trial) . Merriam-Webster Medical Dictionary . 20 November 2020 . 2020.
3. Web site: Double-blind study . HIV.gov, Office of AIDS Research, US National Institutes of Health . 20 November 2020 . 2020.
4. Beyer-Westendorf . J. . Buller. H. . External and internal validity of open label or double-blind trials in oral anticoagulation: better, worse or just different? . Journal of Thrombosis and Haemostasis . 9 . 11 . 2011 . 1538-7933 . 10.1111/j.1538-7836.2011.04507.x . 2153–2158. 21920015 . free .
5. Ballou . Sarah . Kaptchuk . Ted J. . Hirsch . William . Nee . Judy . Iturrino . Johanna . Hall . Kathryn T. . Kelley . John M. . Cheng . Vivian . Kirsch . Irving . Jacobson . Eric . Conboy . Lisa . Lembo . Anthony . Davis . Roger B. . Open-label versus double-blind placebo treatment in irritable bowel syndrome: study protocol for a randomized controlled trial . Trials . 18 . 1 . 25 May 2017 . 234 . 1745-6215 . 10.1186/s13063-017-1964-x . 28545508 . 5445390 . free .