The Hawthorne Effect: a randomised, controlled trial
By R. McCarney, James Warner, S. Iliffe, R. van Haselen, M. Griffin, P. Fisher. BMC Medical Research Methodology, 2007
1,125 citations recorded by the source corpus.
BackgroundThe 'Hawthorne Effect' may be an important factor affecting the generalisability of clinical research to routine practice, but has been little studied. Hawthorne Effects have been reported in previous clinical trials in dementia but to our knowledge, no attempt has been made to quantify them. Our aim was to compare minimal follow-up to intensive follow-up in participants in a placebo controlled trial of Ginkgo biloba for treating mild-moderate dementia.MethodsParticipants in a dementia trial were randomised to intensive follow-up (with comprehensive assessment visits at baseline and two, four and six months post randomisation) or minimal follow-up (with an abbreviated assessment at baseline and a full assessment at six months). Our primary outcomes were cognitive functioning (ADAS-Cog) and participant and carer-rated quality of life (QOL-AD).ResultsWe recruited 176 participants, mainly through general practices. The main analysis was based on Intention to treat (ITT), with available data. In the ANCOVA model with baseline score as a co-variate, follow-up group had a significant effect on outcome at six months on the ADAS-Cog score (n = 140; mean difference = -2.018; 95%CI -3.914, -0.121; p = 0.037 favouring the intensive follow-up group), and on participant-rated quality of life score (n = 142; mean difference = -1.382; 95%CI -2.642, -0.122; p = 0.032 favouring minimal follow-up group). There was no significant difference on carer quality of life.ConclusionWe found that more intensive follow-up of individuals in a placebo-controlled clinical trial of Ginkgo biloba for treating mild-moderate dementia resulted in a better outcome than minimal follow-up, as measured by their cognitive functioning.Trial registrationCurrent controlled trials: ISRCTN45577048
Subfields: Complementary and alternative medicine, Plant Science, Psychiatry and Mental health
View Paper: https://www.semanticscholar.org/paper/cfd6fe984207aa95b6e38b61c86c8a3126858cbb
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In Complementary and alternative medicine
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Citations in the corpus
- Suggestion, Cognition, and Behavior (2012, background): “…in one study of patients with mild dementia, daily administration of Gingko biloba for 6 months had no effect over a placebo—but patients who received several intensive follow-up assessments improved more than did patients who were assessed only at the end of the study (McCarney et al., 2007).”
- Social Media data: Challenges, opportunities and limitations in urban studies (2019, neutral): “This is an advantage because according to the Hawthorne effect, subjects may alter their behaviour in a study on realization that they are being observed (McCarney, Warner, Iliffe, van Haselen, R Griffin, & Fisher, 2007).”
- Is working memory training effective? (2012, background): “In other words, Hawthorne phenomena introduce a general effect of the influences contained within an experiment (Klingberg, 2010; McCarney et al., 2007; Oken et al., 2008; Shipstead et al., 2010).”
- A Usability Evaluation of Tor Launcher (2017, background): “Participants in a laboratory setting may alter their behavior due to their awareness of being observed [26].”