한국임상수의학회지 (Journal of Veterinary Clinics)

  • 제29권1호
  • /
  • Pages.68-77
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  • 2012
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  • 1598-298X(pISSN)
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  • 2384-0749(eISSN)
한국임상수의학회 (The Korean Society of Veterinary Clinics)
권호 표지

의학연구에서 표본크기 계산

Sample Size Calculation in Medical Research

  • 박선일 (강원대학교 수의과대학 및 동물의학종합연구소) ;
  • 오태호 (경북대학교 수의과대학)
  • Pak, Son-Il (College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University) ;
  • Oh, Tae-Ho (College of Veterinary Medicine, Kyungpook National University)
  • 심사 : 2011.12.13
  • 발행 : 2012.02.29
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초록

Whenever planning a study design or preparing a research proposal it is highly recommended that investigators decide the optimum sample size that is required to yield an outcome of interest with a predetermined level of precision. This is because that, all else being equal, if a study with less than the optimum sample size would not detect the significance of differences in reality, and similarly, if a study with more than the optimum sample size will be costly. For these reasons, the majority of peer reviewed biomedical journals assess the adequacy of sample size requirements. The calculated sample size is used as a target number of samples to be collected to provide an estimate of the parameter with the desired and predetermined level of accuracy, and the sample size is a major determinant of the probability of detecting diseased animals from the population. There is no single method of calculating sample size for any given study design. In this context, the purpose of this article is to provide a collection of formulas and examples for some typical situations likely to be encountered in veterinary clinical practice and to highlight the importance of performing prospective sample size calculations when planning a research. Specifically, this paper is concerned with the basic principle of sample size calculation, and considerations for methodological applications were illustrated for a given data set. Also included in this paper is factors influencing sample size calculations using a statistically valid techniques. Appropriate methods to consider these factors are presented.

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참고문헌

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