How to determine Sample Size: the Design of Sample Size in Health Studies
Abstract
Sample-size determination is often an important step in planning a health study—and it is usually a difficult one. Among the important hurdles to be surpassed, one must obtain an estimate of one or more error variances, and specify an effect size of importance. This paper offers some suggestions for successful and meaningful sample-size determination. Also discussed is the possibility that a sample size may not be the main issue and that the real goal is to design a high-quality study. Finally, criticism is made of some ill-advised shortcuts relating to testing power and sample size.
References
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2-Bailar III and F. Mosteller , chap. 14, pp. 289–304, NEJM Books, Waltham, Mass.
3-Boen, J. R. and Zahn, D. A. (1982), The Human Side of Statistical Consulting, Lifetime Learning Publications, Belmont, CA.
4-Borenstein, M., Rothstein, H., and Cohen, J. (1997), Power and Precision, Biostat, Teaneck, NJ, Softwarefor MS-DOS systems.
5-Castelloe, J. (2000), “Sample Size Computations and Power Analysis with the SAS System,” in Proceedingsof the Twenty-Fifth Annual SAS User’s Group International Conference, Cary, NC, SAS Institute, Inc., Paper 265-25.
6-Cochran, W.G. (1977) Sampling Techniques,. Wiley Pub., 3rd edition, New York.
6- Cohen, J. (1988), Statistical Power Analysis for the Behavioral Sciences, Academic Press, New York, 2nd edn.
7-Dallal,Gerard, E.1997, ww.tufts.edu/~gdallal/SIZE.HTM
8- Desu, M. M. and Raghavarao, D. (1990), Sample Size Methodology, Academic Press, Boston.
9-Elashoff, J. (2000), nQuery Advisor Release 4.0, Statistical Solutions, Cork, Ireland, Software for MS-DOS systems.
10-Freiman, J. A., Chalmers, T. C., Smith, Jr., H., and Kuebler, R. R. (1986), “The Importance of Beta, the Type II Error, and Sample Size in the Design and Interpretation of the Randomized Controlled Trial:
Survey of 71 “Negative” Trials,” in Medical Uses of Statistics, eds. J. C.
11-Hintze, J. (2000), PASS 2000, Number Cruncher Statistical Systems, Kaysville, UT, Software for MS-DOS systems.
12-Hoenig, J. M. and Heisey, D. M. (2001), “The Abuse of Power: The Pervasive Fallacy of Power Calculations in Data Analysis,” The American Statistician, 55, 19–24.
13- Kish, Leslie. 1965. Survey Sampling. New York: John Wiley and Sons, Inc.
14-Kraemer, H. C. and Thiemann, S. (1987), How Many Subjects? Statistical Power Analysis in Research, Sage Publications, Newbury Park, CA.
15- Sudman, Seymour. 1976. Applied Sampling. New York: Academic Press.
16- Yamane, Taro. 1967. Statistics, An Introductory Analysis, 2nd Ed., New York: Harper and Row.
Published
2011-06-01
How to Cite
ELDAWI AHMED, Eihab Abdel Rahim; MAHFOUZ, Mohamed Salih; OMER FDUL, Isam.
How to determine Sample Size: the Design of Sample Size in Health Studies.
Gezira Journal of Health Sciences, [S.l.], v. 7, n. 2, june 2011.
ISSN 1810-5386. Available at: <http://37.60.236.48/index.php/gjhs/article/view/321>. Date accessed: 03 june 2026.
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