Determining sample size for pilot trials: a tutorial

Xiangji Ying; Kenneth E Freedland; Lynda H Powell; Elizabeth A Stuart; Stephan Ehrhardt; Evan Mayo-Wilson

doi:10.1136/bmj-2024-083405

journal article Aug 08, 2025

Determining sample size for pilot trials: a tutorial

Xiangji Ying

Kenneth E Freedland Lynda H Powell Elizabeth A Stuart Stephan Ehrhardt Evan Mayo-Wilson

BMJ Vol. 390 pp. e083405 · BMJ

View at Publisher Save 10.1136/bmj-2024-083405

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Details

Published: Aug 08, 2025
Vol/Issue: 390
Pages: e083405
License: View

Authors

X

Xiangji Ying

Department of Epidemiology, University of North Carolina Gillings School of Global Public Health, Chapel Hill, NC 27599, USA

K

Kenneth E Freedland

Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA

L

Lynda H Powell

Department of Family and Preventive Medicine, Rush University Medical Center, Chicago, IL, USA

E

Elizabeth A Stuart

Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MA, USA

S

Stephan Ehrhardt

Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MA, USA

E

Evan Mayo-Wilson

Department of Epidemiology, University of North Carolina Gillings School of Global Public Health, Chapel Hill, NC 27599, USA

Cite This Article

Xiangji Ying, Kenneth E Freedland, Lynda H Powell, et al. (2025). Determining sample size for pilot trials: a tutorial. BMJ, 390, e083405. https://doi.org/10.1136/bmj-2024-083405

Determining sample size for pilot trials: a tutorial

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