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Cited by 122Ethics in Clinical ResearchStatistical Methods in EpidemiologySurvey Methodology and Nonresponse

Survey among 78 studies showed that Lasagna's law holds in Dutch primary care research

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van der Wouden, Johannes C., Blankenstein, Annette H., Huibers, Marcus J.H., van der Windt, Danielle A.W.M., Stalman, Wim A.B., Verhagen, Arianne P.·2007·Journal of Clinical Epidemiology
DOI 10.1016/j.jclinepi.2006.11.010
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Abstract

Objective Research in general practice has grown considerably over the past decades, but many projects face problems when recruiting patients. Lasagna's Law states that medical investigators overestimate the number of patients available for a research study. We aimed to assess factors related to success or failure of recruitment in general practice research.Study design and setting Survey among investigators involved in primary care research in The Netherlands. Face-to-face interviews were held with investigators of 78 projects, assessing study design and fieldwork characteristics as well as success of patient recruitment.Results Studies that focused on prevalent cases were more successful than studies that required incident cases. Studies in which the general practitioner (GP) had to be alert during consultations were less successful. When the GP or practice assistant was the first to inform the patient about the study, patient recruitment was less successful than when the patient received a letter by mail. There was a strong association among these three factors.Conclusion Lasagna's Law also holds in Dutch primary care research: many studies face recruitment problems. Awareness of study characteristics affecting participation of GPs and patients may help investigators to improve their study design.

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Authors
van der Wouden, J. C., Blankenstein, A. H., Huibers, M. J. H., van der Windt, D. A. W. M., Stalman, W. A. B., & Verhagen, A. P.
Affiliations
  • Amsterdam Public Health (NL)
  • Maastricht University (NL)
  • Erasmus MC (NL)
ORCID
Venue
Journal of Clinical Epidemiology
Publisher
Elsevier BV
Published
2007-08
Volume
60
Issue
8
Pages
819-824
ISSN
0895-4356 (ISSN-L)
DOI
10.1016/j.jclinepi.2006.11.010
OpenAlex
W2090045350
Cited by
122
References
16
Citations by year
2026: 3 · 2025: 4 · 2024: 4 · 2023: 4 · 2022: 1 · 2021: 6 · 2020: 6 · 2019: 5 · 2018: 4 · 2017: 6 · 2016: 6 · 2015: 9 · 2014: 11 · 2013: 9 · 2012: 11
FWCI
9.27
Type
journal article
Language
en
Open access
Licence
Locations
  • Journal of Clinical Epidemiology (publishedVersion)
  • PubMed (publishedVersion)
  • Research Publications (Maastricht University) (publishedVersion, other-oa)
  • Pure Amsterdam UMC (publishedVersion)
  • Amsterdam UMC (VU Amsterdam) - Institutional Repository (publishedVersion, other-oa)
  • EUR Research Repository (Erasmus University Rotterdam) (publishedVersion)
  • EUR Research Repository (Erasmus University Rotterdam) (submittedVersion)
  • Digital Academic REpository of VU University Amsterdam (Vrije Universiteit Amsterdam) (submittedVersion)
  • Research Publications (Maastricht University) (submittedVersion)
  • Data Archiving and Networked Services (DANS) (submittedVersion)
  • Data Archiving and Networked Services (DANS) (submittedVersion, other-oa)
Funders
ZonMw
Topics
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Ethics in Clinical Research
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Epidemiology
  • Social Sciences › Sociology and Political Science › Survey Methodology and Nonresponse
Keywords
patient recruitment, primary care research, general practice, research design, research participation
MeSH terms
Humans, Interviews as Topic, Physician-Patient Relations, Physicians, Family, Postal Service, Primary Health Care, Research Design, Research Personnel, Time Factors, Sample Size, Patient Selection

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