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Cited by 255

The DOI matches its Crossref record; 9 of the 9 references it cites were found in a registry or an index.

Recruiting patients to medical research: double blind randomised trial of “opt-in” versus “opt-out” strategies

Open access
Junghans, Cornelia, Feder, Gene, Hemingway, Harry, Timmis, Adam, Jones, Melvyn·2005·BMJ
DOI 10.1136/bmj.38583.625613.ae
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Abstract

OBJECTIVE: To evaluate the effect of opt-in compared with opt-out recruitment strategies on response rate and selection bias. DESIGN: Double blind randomised controlled trial. SETTING: Two general practices in England. PARTICIPANTS: 510 patients with angina. INTERVENTION: Patients were randomly allocated to an opt-in (asked to actively signal willingness to participate in research) or opt-out (contacted repeatedly unless they signalled unwillingness to participate) approach for recruitment to an observational prognostic study of patients with angina. MAIN OUTCOME MEASURES: Recruitment rate and clinical characteristics of patients. RESULTS: The recruitment rate, defined by clinic attendance, was 38% (96/252) in the opt-in arm and 50% (128/258) in the opt-out arm (P = 0.014). Once an appointment had been made, non-attendance at the clinic was similar (20% opt-in arm v 17% opt-out arm; P = 0.86). Patients in the opt-in arm had fewer risk factors (44% v 60%; P = 0.053), less treatment for angina (69% v 82%; P = 0.010), and less functional impairment (9% v 20%; P = 0.023) than patients in the opt-out arm. CONCLUSIONS: The opt-in approach to participant recruitment, increasingly required by ethics committees, resulted in lower response rates and a biased sample. We propose that the opt-out approach should be the default recruitment strategy for studies with low risk to participants.

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Metadata

Authors
Junghans, C., Feder, G., Hemingway, H., Timmis, A., & Jones, M.
Venue
BMJ
Publisher
BMJ
Published
2005-09-12
Volume
331
Issue
7522
Pages
940
ISSN
  • 0007-1447 (ISSN-L)
  • 0959-8138
  • 1468-5833
DOI
10.1136/bmj.38583.625613.ae
OpenAlex
W2049188870
Cited by
255
References
9
FWCI
14.23
Type
journal article
Language
en
Open access
bronze

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CoChat. (2026). Citation check: Recruiting patients to medical research: double blind randomised trial of “opt-in” versus “opt-out” strategies. https://app.cochat.ai/papers/10.1136/bmj.38583.625613.ae
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Junghans, C., Feder, G., Hemingway, H., Timmis, A., & Jones, M. (2005). Recruiting patients to medical research: double blind randomised trial of “opt-in” versus “opt-out” strategies. BMJ. https://doi.org/10.1136/bmj.38583.625613.ae

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