摘要目的:分析晋中市县级碘缺乏病实验室盐碘监测复核结果，了解县级实验室监测质量，为制定碘缺乏病防控策略提供科学依据。方法:2021 - 2023年，晋中市疾病预防控制中心采用系统随机抽样法，每年抽取所辖每个县级碘缺乏病实验室（共11个）检测的所有食用盐盐样的5%（各15份），进行复核检测。盐碘检测均采用《制盐工业通用试验方法　碘的测定》（GB/T 13025.7-2012）氧化还原滴定法。计数资料组间比较采用χ 2检验，计量资料组间比较采用随机成组设计 t检验进行分析。 结果:2021 - 2023年，市级实验室每年抽取165份食用盐盐样（3年共495份）进行复核检测。县级实验室检测的合格碘盐食用率为92.53%（458/495），各年度分别为89.70%（148/165）、93.33%（154/165）、94.55%（156/165）；市级实验室检测的合格碘盐食用率为94.95%（470/495），各年度分别为90.91%（150/165）、96.36%（159/165）、97.58%（161/165）。两级实验室2021 - 2023年检测的合格碘盐食用率比较差异无统计学意义（χ 2 = 2.48， P = 0.116）。2021 - 2023年市级复核县级实验室盐碘检测结果相对误差> 20%的盐样占比分别为20.00%（33/165）、16.97%（28/165）、8.48%（14/165），不同年份间比较差异有统计学意义（χ 2 = 8.49， P = 0.004），2021、2022年分别与2023年比较，差异均有统计学意义（均 P < 0.05）；相对误差> 30%的盐样占比分别为7.88%（13/165）、6.06%（10/165）、3.64%（6/165），三者间比较差异无统计学意义（χ 2 = 2.69， P = 0.101）。两级实验室检测结果成组数据比较，差异有统计学意义（ t = 6.05， P < 0.001）。复核结果成组数据中，共16组有统计学意义，其中2021年4组、2022年7组、2023年5组。 结论:复核结果表明，晋中市县级碘缺乏病实验室盐碘监测质量不断提高，检测数据真实可信。今后应加大对县级实验室检验人员的培训，提升实验人员的操作技能，最大限度降低检测结果误差。

abstractsObjective:To analyze the review results of salt iodine monitoring in the county-level laboratories of iodine deficiency disorders in Jinzhong City, and to learn about the quality of the monitoring in the county-level laboratories, so as to provide scientific basis for formulating iodine deficiency disorders prevention and control strategies.Methods:From 2021 to 2023, Jinzhong Center for Disease Control and Prevention used the systematic random sampling method to select 5% (15 samples each) of all edible salt samples (short for salt samples) tested by 11 county-level iodine deficiency disorders laboratories under its jurisdiction for retesting each year. The salt iodine was determined by the redox titration method in accordance with the "General Test Method in Salt Industry-Determination of Iodine" (GB/T 13025.7-2012). Comparisons between groups for count data were analyzed using the χ 2 test, and the comparisons between groups for measurement data were analyzed using a random group design t-test. Results:From 2021 to 2023, the municipal laboratories reviewed and tested 165 salt samples (495 in total over 3 years). The proportion of households using adquately iodized salt tested by county-level laboratories was 92.53% (458/495), with annual rates of 89.70% (148/165), 93.33% (154/165), and 94.55% (156/165), respectively. The proportion of households using adquately iodized salt detected by municipal laboratories was 94.95% (470/495), with annual rates of 90.91% (150/165), 96.36% (159/165), and 97.58% (161/165), respectively. There was no significant difference in the proportion of households using adquately iodized salt detected by the two-level laboratories from 2021 to 2023 (χ 2 = 2.48, P = 0.116). The proportion of salt samples with relative error > 20% in the salt iodine detection results of county-level laboratories reviewed at the municipal laboratory from 2021 to 2023 were 20.00% (33/165), 16.97% (28/165), and 8.48% (14/165), respectively. The differences between different years were statistically significant (χ 2 = 8.49, P = 0.004). Compared with 2023, in 2021 and 2022, the differences were statistically significant ( P < 0.05). The proportion of salt samples with relative error > 30% were 7.88% (13/165), 6.06% (10/165), and 3.64% (6/165), respectively. There was no significant difference among different years (χ 2 = 2.69, P = 0.101). The comparison of laboratory test results between the two-level laboratories showed statistically significant differences ( t = 6.05, P < 0.001). Among the group data reviewed, there were a total of 16 groups with statistical significance, including 4 groups in 2021, 7 groups in 2022, and 5 groups in 2023. Conclusions:The review results indicate that the quality of salt iodine monitoring in county-level laboratories in Jinzhong City continues to improve, and the testing data are authentic and reliable. In the future, training for county-level laboratory inspectors should be increased to enhance their operational skills and minimize testing result errors.