@article{ref1,
title="Randomised trial seeking to induce the Hawthorne effect found no evidence for any effect on self-reported alcohol consumption online",
journal="Journal of clinical epidemiology",
year="2019",
author="McCambridge, Jim and Wilson, Amanda and Attia, John and Weaver, Natasha and Kypri, Kypros",
volume="108",
number="",
pages="102-109",
abstract="OBJECTIVE: We tested the hypothesis that participants who know the behavioural focus of a study and are thus aware that a particular behaviour is being studied, will modify that behaviour, independently of any possible effect of assessment, thereby dismantling a Hawthorne effect into two putative components. STUDY DESIGN AND SETTING: We undertook a three-arm individually randomised trial online among students: Group A (control) were told they were completing a lifestyle survey; Group B were told the focus of the survey was alcohol consumption; Group C additionally answered 20 questions on their alcohol use and its consequences before answering the same lifestyle questions as Groups A and B. Non-drinkers were excluded and all groups were aware they would be followed-up after one month. <br><br>RESULTS: Outcome data were obtained for 4583/5478 trial participants (84% follow-up rate). There were no differences between the three groups on primary (overall volume consumed) or secondary outcome measures (drinking frequency and amount per typical occasion) in the intervening four weeks. <br><br>CONCLUSIONS: There is no evidence that any form of Hawthorne effect exists in relation to self-reported alcohol consumption online among university students in usual research practice. Attention to study contexts is warranted for investigating research participation effects.<br><br>Copyright © 2018. Published by Elsevier Inc.<p /> <p>Language: en</p>",
language="en",
issn="0895-4356",
doi="10.1016/j.jclinepi.2018.11.016",
url="http://dx.doi.org/10.1016/j.jclinepi.2018.11.016"
}