Estimation of Sample Size for Reference Interval Studies

✍ Scribed by James F. Troendle; Kai F. Yu

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 97 KB
• Volume: 45
• Category: Article
• ISSN: 0323-3847
• DOI: 10.1002/bimj.200390033

✦ Synopsis

Abstract

The currently used criterion for sample size calculation in a reference interval study is not well stated and leads to imprecise control of the ratio in question. We propose a generalization of the criterion used to determine sufficient sample size in reference interval studies. The generalization allows better estimation of the required sample size when the reference interval estimation will be using a power transformation or is nonparametric. Bootstrap methods are presented to estimate sample sizes required by the generalized criterion. Simulation of several distributions both symmetric and positively skewed is presented to compare the sample size estimators. The new method is illustrated on a data set of plasma glucose values from a 50‐g oral glucose tolerance test. It is seen that the sample sizes calculated from the generalized criterion leads to more reliable control of the desired ratio.