Cited by 612Statistical Methods in EpidemiologyStatistical Methods in Clinical TrialsMeta-analysis and systematic reviews

A simple formula for the calculation of sample size in pilot studies

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Viechtbauer, Wolfgang, Smits, Luc, Kotz, Daniel, Budé, Luc, Spigt, Mark, Serroyen, Jan, Crutzen, Rik·2015·Journal of Clinical Epidemiology

Abstract

One of the goals of a pilot study is to identify unforeseen problems, such as ambiguous inclusion or exclusion criteria or misinterpretations of questionnaire items. Although sample size calculation methods for pilot studies have been proposed, none of them are directed at the goal of problem detection. In this article, we present a simple formula to calculate the sample size needed to be able to identify, with a chosen level of confidence, problems that may arise with a given probability. If a problem exists with 5% probability in a potential study participant, the problem will almost certainly be identified (with 95% confidence) in a pilot study including 59 participants.

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Crossref · 10.1016/j.jclinepi.2015.04.014

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  1. Institute of Laboratory Animal Resources. Long-term holding of lab- oratory rodents. ILAR News 1976;19:1e25.

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Authors
Viechtbauer, W., Smits, L., Kotz, D., Budé, L., Spigt, M., Serroyen, J., & Crutzen, R.
Affiliations
Maastricht University (NL)
Corresponding author
Crutzen, Rik
Venue
Journal of Clinical Epidemiology
Publisher
Elsevier BV
Published
2015-11
Volume
68
Issue
11
Pages
1375-1379
ISSN
0895-4356 (ISSN-L)
OpenAlex
W1763526952
Cited by
612
References
15
Citations by year
2026: 56 · 2025: 91 · 2024: 93 · 2023: 82 · 2022: 77 · 2021: 69 · 2020: 50 · 2019: 39 · 2018: 31 · 2017: 16 · 2016: 8
FWCI
16.32
Type
journal article
Language
en
Open access
Locations
  • Journal of Clinical Epidemiology (publishedVersion)
  • PubMed (publishedVersion)
  • Research Publications (Maastricht University) (publishedVersion, other-oa)
  • Lirias (submittedVersion)
  • Research Publications (Maastricht University) (submittedVersion, other-oa)
Topics
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Epidemiology
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Clinical Trials
  • Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
Keywords
sample size determination, pilot study, problem identification, inclusion and exclusion criteria, statistical power
MeSH terms
Humans, Pilot Projects, Sample Size, Mathematical Concepts

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