Measuring the success of blinding in placebo-controlled trials: Should we be so quick to dismiss it?

What's new•Blinding in clinical trials has the potential to reduce bias.•There is a live yet underreported debate about the value of measuring blinding success.•Interpreting the success of blinding can be problematic and potentially misleading.•However, failure to report the success of blinding...

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Published in:Journal of clinical epidemiology 2021-07, Vol.135, p.176-181
Main Authors: Webster, Rebecca K., Bishop, Felicity, Collins, Gary S., Evers, Andrea W.M., Hoffmann, Tammy, Knottnerus, J. André, Lamb, Sarah E., Macdonald, Helen, Madigan, Claire, Napadow, Vitaly, Price, Amy, Rees, Jonathan L., Howick, Jeremy
Format: Article
Language:English
Subjects:
Blinding
Clinical trials
Clinical Trials as Topic - methods
Double-Blind Method
Epidemiology
Humans
Intervention
Masking
Measuring
Placebo Effect
Placebos
Reporting guidelines
Research Design
Single-Blind Method
Stroke
Success
Trials
Vitamin C
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container_issue
container_start_page 176
container_title Journal of clinical epidemiology
container_volume 135
creator Webster, Rebecca K.
Bishop, Felicity
Collins, Gary S.
Evers, Andrea W.M.
Hoffmann, Tammy
Knottnerus, J. André
Lamb, Sarah E.
Macdonald, Helen
Madigan, Claire
Napadow, Vitaly
Price, Amy
Rees, Jonathan L.
Howick, Jeremy
description What's new•Blinding in clinical trials has the potential to reduce bias.•There is a live yet underreported debate about the value of measuring blinding success.•Interpreting the success of blinding can be problematic and potentially misleading.•However, failure to report the success of blinding, if it is measured, seems like willful withholding of information that is at least potentially useful.•We suggest a middle road whereby the success of blinding be measured (where feasible) and interpreted with caution. ‘Blinding’ involves concealing knowledge of which trial participants received the interventions from participants themselves and other trial personnel throughout the trial. Blinding reduces bias arising from the beliefs and expectations of these groups. It is agreed that where possible, blinding should be attempted, for example by ensuring that experimental and control treatments look the same. However, there is a debate about if we should measure whether blinding has been successful, this manuscript will discuss this controversy, including the benefits and risks of measuring blinding within the randomised controlled trial.
doi_str_mv 10.1016/j.jclinepi.2021.02.022
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subjects Blinding
Clinical trials
Clinical Trials as Topic - methods
Double-Blind Method
Epidemiology
Humans
Intervention
Masking
Measuring
Placebo Effect
Placebos
Reporting guidelines
Research Design
Single-Blind Method
Stroke
Success
Trials
Vitamin C
title Measuring the success of blinding in placebo-controlled trials: Should we be so quick to dismiss it?
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