Abstract:
The Grubbs statistical method, the median and normalized interquartile range method and the iterative method are three commonly used statistical analysis methods for proficiency testing results. A comparison was made for above-mentioned three methods and the analytical results showed that when the data conformed to or basically conformed to the normal distribution, the iterative method was more reliable. When the data did not conform to the normal distribution, the median and standardized interquartile range methods and the iterative method would be not applicable, whereas more reasonable statistical results could be obtained by using the Grubbs statistic method and adopting an appropriate elimination level
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