A Comparison of Sample Size Requirements for Intraclass Correlation Coefficient(ICC) Han, Soo-Yeon; Nam, Jung-Mo; Myoung, Sung-Min; Song, Ki-Jun;
In medical practice and research, the problem of assessing reliability between two or more quantitative measures is quite common. Intraclass correlation coefficient(ICC) is commonly used to scale of reliability. Some methods were developed to calculate the required number of subjects, raters or replicates in one-way or two-way random ANOVA models. This paper, studies and compares the performance of four methods such as Walter et al. (1998), Giraudeau and Mary (2001), Saito et al. (2006) and Bonett (2002). In order to compare the efficiency of methods we compare the number of subjects, replicates and the width of confidence interval of ICC needed for some specific ICC values. In the case of subject size, Giraudeau`s method is the best. In case of the number of replicates, Saito`s method was superior to others. The width of confidence interval of ICC was narrower for Giraudeau`s method than any others.
The Journal of Korean Physical Therapy, 2011. vol.23. 4, pp.59-66
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