Related Experiment Video
Updated: Oct 29, 2025

Precision Implementation of Minimal Erythema Dose MED Testing to Assess Individual Variation in Human Inflammatory Response
Published on: October 3, 2019
Reducing bias in trials due to reactions to measurement: experts produced recommendations informed by evidence
David P French1, Lisa M Miles1, Diana Elbourne2
1Manchester Centre for Health Psychology, University of Manchester, Oxford Road, Manchester, UK.
Objective:
This study (MEasurement Reactions In Trials) aimed to produce recommendations on how best to minimize bias from measurement reactivity (MR) in randomized controlled trials of interventions to improve health.
Study Design And Setting:
The MERIT study consisted of: (1) an updated systematic review that examined whether measuring participants had effects on participants' health-related behaviors, relative to no-measurement controls, and three rapid reviews to identify: (i) existing guidance on MR; (ii) existing systematic reviews of studies that have quantified the effects of measurement on behavioral or affective outcomes; and (iii) studies that have investigated the effects of objective measurements of behavior on health-related behavior; (2) a Delphi study to identify the scope of the recommendations; and (3) an expert workshop in October 2018 to discuss potential recommendations in groups.
Results:
Fourteen recommendations were produced by the expert group to: (1) identify whether bias is likely to be a problem for a trial; (2) decide whether to collect data about whether bias is likely to be a problem; (3) design trials to minimize the likelihood of this bias.
Conclusion:
These recommendations raise awareness of how and where taking measurements can produce bias in trials, and are thus helpful for trial design.
Related Concept Videos
Blind Procedures
Bias in Epidemiological Studies
Bias
In statistics, a sampling bias is created when a sample is collected from a population, and some members of the population are not as likely to be chosen as others (remember, each member...
Blinding
Halo Effect
Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast,...

