Estimating sample sizes for binary, ordered categorical, and continuous outcomes in two group comparisons.
Journal articles
- Journal Article, Review
Campbell, MJ; Julious, SA; Altman, DG
Published in: BMJ
October 28, 1995
Sample size calculations are now mandatory for many research protocols, but the ones useful in common situations are not all easily accessible. This paper outlines the ways of calculating sample sizes in two group studies for binary, ordered categorical, and continuous outcomes. Formulas and worked examples are given. Maximum power is usually achieved by having equal numbers in the two groups. However, this is not always possible and calculations for unequal group sizes are given.
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Published In
BMJ
DOI
ISSN
0959-8138
Publication Date
October 28, 1995
Volume
311
Issue
7013
Start / End Page
1145 / 1148
Location
England
Related Subject Headings
- Sample Size
- Humans
- General & Internal Medicine
- Data Interpretation, Statistical
- 52 Psychology
- 42 Health sciences
- 32 Biomedical and clinical sciences
Citation
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Chicago
ICMJE
MLA
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Campbell, M. J., Julious, S. A., & Altman, D. G. (1995). Estimating sample sizes for binary, ordered categorical, and continuous outcomes in two group comparisons. BMJ, 311(7013), 1145–1148. https://doi.org/10.1136/bmj.311.7013.1145
Campbell, M. J., S. A. Julious, and D. G. Altman. “Estimating sample sizes for binary, ordered categorical, and continuous outcomes in two group comparisons.” BMJ 311, no. 7013 (October 28, 1995): 1145–48. https://doi.org/10.1136/bmj.311.7013.1145.
Campbell MJ, Julious SA, Altman DG. Estimating sample sizes for binary, ordered categorical, and continuous outcomes in two group comparisons. BMJ. 1995 Oct 28;311(7013):1145–8.
Campbell, M. J., et al. “Estimating sample sizes for binary, ordered categorical, and continuous outcomes in two group comparisons.” BMJ, vol. 311, no. 7013, Oct. 1995, pp. 1145–48. Pubmed, doi:10.1136/bmj.311.7013.1145.
Campbell MJ, Julious SA, Altman DG. Estimating sample sizes for binary, ordered categorical, and continuous outcomes in two group comparisons. BMJ. 1995 Oct 28;311(7013):1145–1148.
Published In
BMJ
DOI
ISSN
0959-8138
Publication Date
October 28, 1995
Volume
311
Issue
7013
Start / End Page
1145 / 1148
Location
England
Related Subject Headings
- Sample Size
- Humans
- General & Internal Medicine
- Data Interpretation, Statistical
- 52 Psychology
- 42 Health sciences
- 32 Biomedical and clinical sciences