Establishment and verification of gender-and age-specific reference intervals of TSH in adults in Xiangtan area based on indirect method
HE Sui
DENG Xinrui
XIAO Jinyuan
CHEN Jinlong
Abstract：Objective To establish and verify gender-and age-specific reference intervals for thyroid stimulating hor-mone(TSH)in adults in Xiangtan area by indirect method,with the expectation of providing more appropriate reference ba-sis for the diagnosis and treatment of thyroid diseases in this region.Methods TSH data of healthy adults aged≥18 years from January 2020 to December 2022 in laboratory information system were collected as the reference interval establishment dataset,and the data from January to June 2023 were collected as the reference interval verification dataset.After prelimi-nary data cleaning,a total of 9,880 TSH data were obtained for the reference interval establishment dataset and 2,076 for the reference interval verification dataset.The normality of the data was tested by Kolmogorov-Smirnov test combined with histogram,and the data were transformed to normal distribution by Box-Cox transformation.Abnormal outliers were identi-fied and removed by Tukey method.Two-level nested ANOVA was used to determine the necessity of gender and age stratifi-cation,and the age cut-off points were determined by Segmented R.The reference intervals were calculated as the P2.5-P97.5 by non-parametric method.The self-established reference intervals were verified by the reference interval verification datas-et,and the proportion of each group falling outside the self-established reference intervals was calculated.Results After removing outliers by Tukey method,a total of 9,393 TSH data were included in the reference interval establishment dataset and 1,976 in the reference interval verification dataset.Two-level nested ANOVA showed that there was little overall differ-ence in TSH levels,but the reference upper limits varied among groups,indicating the need for stratification.The age cut-off points for the male and female were determined as 47 years and 35 years,respectively,by Segmented R.The established TSH reference intervals were as follows:for the male of 18-46 year old,it was(0.70-3.84)μIU/mL,for the male aged 47 and above,it was(0.65-5.80)μIU/mL,for the female of 18-34 year old,it was(0.52-5.26)μIU/mL,for the male aged 35 and above,it was(0.50-6.51)μIU/mL.The lower limits of the self-established reference intervals for each stratum were relatively close,while the upper limits varied greatly.Except for male aged 18-46 years,the self-established intervals were relatively close to the industry standard reference intervals,but relatively different from the manufacturer's reference intervals.In the reference interval verification dataset,the proportion of each group falling outside the self-established refer-ence intervals was all less than 10%,and the compliance rate was≥90%,indicating that the self-established reference inter-vals were applicable to the local population.Conclusions Gender-and age-specific TSH reference intervals in adults in Xiangtan area were successfully established by indirect method.These reference intervals can more accurately evaluate thy-roid function of patients in this region,which is helpful for the diagnosis and treatment of thyroid diseases.
Keywords：thyroid-stimulating hormonelaboratory information systemreference intervalindirect methodXiangtan area
Publication Date：2025-08-25
Online Publishing Date：2025-09-10(First online date of this platform, not the publication date of the document)
Pages：5( 95-98,103 )