环境水体中粪大肠菌群实验室间比对统计方法研究

Inter-laboratory comparison study on statistical techniques of fecal coliform in environmental water

目的 探讨两种不同的统计方法在环境水体粪大肠菌群实验室间比对中的适用性,考察其实际应用情况,并选择科学合理的方法对环境水体中粪大肠菌群的检测能力进行评价分析。方法 采用格拉布斯(Grubbs)检验法和四分位稳健统计法两种统计方法对2021年我国255家生态环境检验检测机构开展的环境水体中粪大肠菌群实验室间比对数据进行统计分析。结果 四分位稳健统计法评价结果中共有11个不满意结果,Grubbs检验法仅发现1个离群值,该离群值与稳健统计法评价结果一致。为减少离群值的影响,采用四分位稳健统计法评价环境水体中粪大肠菌群实验室间比对结果更为科学合理。环境水体中粪大肠菌群实验室间比对结果满意率为90.2%。结论 本次全国生态环境实验室对环境水体中粪大肠菌群的整体检测能力水平较好。

Objective The applicability of the two statistical techniques was discussed and investigated,and the detection capability of fecal coliforms in environment water among eco-environmental institutions in China was analyzed and evaluated by using the selected reasonable method.Methods The inter-laboratory comparison of fecal coliform in environmental water was conducted in 2021 among 255 eco-environmental institutions and analyzed by using Grubbs test and quartile robust statistics.Results There were 11 unsatisfactory results with quartile robust statistics,while only 1 outlier was found by Grubbs test,consistent with quartile robust statistics.It is more scientific and reasonable to use robust statistical technique to evaluate the results of fecal coliforms inter-laboratory comparison in environment water to reduce the influence of outliers.The final evaluation results showed that the satisfaction rate of fecal coliforms in environmental water was 90.2%.Conclusion It is suggested that the detection capability of fecal coliforms in environment water among eco-environmental institutions in China is satisfactory overall.