1.Analysis of the current status and related factors of iodine nutrition levels among adults aged 18 years and above in Zhejiang Province in 2022
Guangming MAO ; Zhe MO ; Simeng GU ; Fanjia GUO ; Yuanyang WANG ; Jiaxin HE ; Yujie JIANG ; Yahui LI ; Zhijian CHEN ; Xiaofeng WANG ; Xiaoming LOU ; Chenyang LIU
Chinese Journal of Preventive Medicine 2025;59(1):22-29
Objective:To analyze the iodine nutrition status and its related factors among adults aged 18 years and above in Zhejiang Province in 2022.Methods:A multistage stratified sampling method was used to select 4 320 adults aged 18 years and above from 16 on-site survey sites in Zhejiang Province for the study. A questionnaire was used to investigate the general demographic information and personal dietary characteristics of the study participants. Household edible salt and urine samples were collected to detect salt iodine content and urinary iodine level by using direct titration and cerium arsenate-catalyzed spectrophotometry, respectively, to evaluate the iodine nutritional status according to the standard. The multiple-ordered logistic regression model was used to analyze the factors influencing the urinary iodine concentration.Results:The age of the 4 320 study participants was (51.19±15.33) years, with males accounting for 44.44% (1 920). About 40.16% of adults (1 735) were from coastal areas and 56.37% (2 435) from urban areas. The salt iodine content, M ( Q1, Q3), of the 4 320 household edible salt samples was 21.10 (0.00, 24.16) mg/kg, including 1 662 non-iodized salt samples, 182 unqualified iodized salt samples and 2 476 qualified iodized salt samples. The rate of iodized salt coverage was 61.53%, and the rate of qualified iodized salt consumption was 57.31%. There was a statistically significant difference in the proportion of qualified iodized salt in adult households among different regions ( P<0.001), with the proportion of non-iodized salt gradually decreasing from coastal to inland areas ( χ 2trend=618.458, P<0.001). The urinary iodine concentration M ( Q1, Q3) was 137.60 (86.85, 210.60) μg/L in 4 320 adult urine samples, with the urinary iodine levels of<100, 100-199, 200-299, and≥300 μg/L accounting for 31.64% (1 367), 40.56% (1 752), 17.66% (763), and 10.14% (438), respectively. There was a nonlinear positive correlation between household salt iodine content and urinary iodine level in adults aged 18 years and above by using the χ 2 test for trend ( χ 2regression=231.10, P<0.001 and χ 2skew=28.81, P<0.001). Urinary iodine concentrations were higher in men than in women ( P=0.029) and higher in adults in rural areas than in urban areas ( P<0.001). There were statistically significant differences in the distribution of iodine nutritional status among adults of different ages, regions, and urban and rural areas (all P<0.001). The proportion of those with urinary iodine levels<100 μg/L gradually increased with age ( χ 2trend=37.493, P<0.001), and gradually decreased from coastal areas to inland areas ( χ 2trend=71.381, P<0.001). The results of the multiple-ordered logistic regression model analysis showed that compared with adults aged 18 to 44 years and male adults, those aged 45 to 59 years and female adults had lower urinary iodine levels, with OR (95% CI) of 0.75 (0.68-0.83) and 0.85 (0.76-0.95), respectively. Compared with adults in coastal and urban adults, those in sub-coastal, inland and rural adults had higher levels of urinary iodine, with OR (95% CI) of 1.89 (1.63-2.19), 2.02 (1.72-2.37) and 1.46 (1.28-1.66), respectively. Conclusion:The overall iodine nutrition level of adults aged 18 years and above in Zhejiang Province in 2022 is generally appropriate. However, there is a potential risk of iodine deficiency among adults in coastal areas.
2.Quantitative analysis of motion of cardiac substructures in deep inspiratory breath holding radiotherapy for left breast cancer
Zhao-hui TANG ; Zhe ZHANG ; Wei-bin MAO ; Bo HUANG ; Jun-feng AI ; Chao-fan ZHU ; Zhi-chao XIE ; Ya-jie LIU
Chinese Medical Equipment Journal 2025;46(3):54-58
Objective To quantify the volume and movement of cardiac substructures by using coronary computed tomography angiography(CCTA)to provide guidance for the design of deep inspiratory breath-holding radiation therapy for left breast cancer and the protection of organs at risk.Methods Totally 18 female patients who received conventional chest plain scan and CCTA were selected to simulate the design process of radiotherapy plan for left breast cancer patients with internal mammary lymph nodes.Retrospective reconstruction of CCTA data was performed for each patient,with 10 phase images(with an interval of 10%)within a R-R cardiac cycle(10%-100%)to simulate the true range of motion of the heart.The heart,left atrium(LA),left ventricle(LV),right atrium(RA),right ventricle(RV),left anterior descending artery(LAD),left circumflex coronary artery(LCX)and right coronary artery(RCA)were contoured at each phase.The distances from the centroid position to the average position of LAD,LCX and RCA were measured at each phase in the superior-inferior(SI),anterior-posterior(AP)and left-right(LR).The average volume and range of volume changes of LA,LV,RA,RV and heart were analyzed within a cardiac cycle.The expansion margins of planning organs at risk volume(PRV)were calculated.SPSS 19.0 software was used for statistical analysis.Results The following average absolute displacements were found in SI,AP and LR coordinates:(1.8±0.7)mm,(1.2±0.5)mm and(1.5±0.5)mm for LAD,respectively;(2.1±0.7)mm,(1.5±0.6)mm and(1.9±0.7)mm for LCX,respectively;(1.6±0.5)mm,(2.2±0.9)mm and(2.2±0.8)mm for RCA,respectively.The volume changes of LA,LV,RA,RV and heart within a cardiac cycle ranged from 34.3 to 63.9 cm3,122.1 to 154.3 cm3,29.3 to 53.6 cm3,57.2 to 94.3 cm3 and 480.1 to 515.4 cm3,respectively.The theoretical expansion margins of LAD,LCX and RCA in all the three directions were within 2 mm.Conclusion The ranges of movement and volume changes of cardiac substructure are quantitati-vely displayed,and references are provided for the planning of deep inspiratory breath-holding radiation therapy for left breast cancer and the protection of organs at risk.[Chinese Medical Equipment Journal,2025,46(3):54-58]
3.Diagnosis and treatment guideline for acute cervical spinal cord injury without fracture-dislocation in adults (version 2025)
Qingde WANG ; Tongwei CHU ; Jian DONG ; Liangjie DU ; Haoyu FENG ; Shunwu FAN ; Shiqing FENG ; Yanzheng GAO ; Yong HAI ; Da HE ; Dianming JIANG ; Jianyuan JIANG ; Bin LIN ; Bin LIU ; Baoge LIU ; Fang LI ; Feng LI ; Li LI ; Weishi LI ; Fangcai LI ; Xiaoguang LIU ; Hongjian LIU ; Yong LIU ; Zhongjun LIU ; Shibao LU ; Xuhua LU ; Keya MAO ; Xuexiao MA ; Yong QIU ; Limin RONG ; Jun SHU ; Yueming SONG ; Tiansheng SUN ; Yan WANG ; Zhe WANG ; Zheng WANG ; Bing WANG ; Linfeng WANG ; Yu WANG ; Qinghe WANG ; Jigong WU ; Hong XIA ; Guoyong YIN ; Jinglong YAN ; Wen YUAN ; Yong YANG ; Qiang YANG ; Cao YANG ; Jie ZHAO ; Jianguo ZHANG ; Yue ZHU ; Zezhang ZHU ; Yingjie ZHOU ; Zhongmin ZHANG ; Yan ZENG ; Dingjun HAO ; Baorong HE ; Wei MEI
Chinese Journal of Trauma 2025;41(3):243-252
Cervical spinal cord injury without fracture-dislocation (CSCIWFD) is referred to as a special type of cervical spinal cord injury characterized by traumatic spinal cord dysfunction and no significant bony structural abnormalities on imagines. Duo to the high risk of missed diagnosis during the initial consultation, CSCIWFD may lead to progressive neurological deterioration or even complete paralysis, severely impacting patients′ prognosis. Currently, there are no established consensuses over the diagnosis and treatment of CSCIWFD, such as the lack of evidence-based standards for indications of non-surgical treatment and risk of secondary neurological injury, as well as debates over the optimal timing for surgical intervention and indications for different surgical approaches. To address these issues, the Spine Trauma Group of the Orthopedic Branch of the Chinese Medical Doctor Association organized experts in the relevant fields to formulate Diagnosis and treatment guideline for acute cervical spinal cord injury without fracture- dislocation in adults ( version 2025) . Based on evidence-based medicine and the principles of scientific rigor and clinical applicability, the guidelines proposed 11 recommendations covering terminology, diagnosis, evaluation treatment, and rehabilitation, etc., aiming to standardize the management of CSCIWFD.
4.Bone Age Estimation of Chinese Han Adolescents's and Children's Elbow Joint X-rays Based on Multiple Deep Convolutional Neural Network Models
Dan-Yang LI ; Hui-Ming ZHOU ; Lei WAN ; Tai-Ang LIU ; Yuan-Zhe LI ; Mao-Wen WANG ; Ya-Hui WANG
Journal of Forensic Medicine 2025;41(1):48-58
Objective To explore a deep learning-based automatic bone age estimation model for elbow joint X-ray images of Chinese Han adolescents and children and evaluate its performance.Methods A total of 943(517 males and 426 females)elbow joint frontal view X-ray images of Chinese Han ado-lescents and children aged 6.00 to<16.00 years were collected from East,South,Central and North-west China.Three experimental schemes were adopted for bone age estimation.Scheme 1:Directly in-put preprocessed images into the regression model;Scheme 2:Train a segmentation network using"key elbow joint bone annotations"as labels,then input segmented images into the regression model;Scheme 3:Train a segmentation network using"full elbow joint bone annotations"as labels,then in-put segmented images into the regression model.For segmentation,the optimal model was selected from U-Net,UNet++and TransUNet.For regression,VGG16,VGG19,InceptionV2,InceptionV3,ResNet34,ResNet50,ResNet101 and DenseNet121 models were selected for bone age estimation.The dataset was randomly split into 80%(754 samples)for training and validation for model fitting and hyperparameter tuning,and 20%(189 samples)as an internal test set to test the performance of the trained model.An additional 104 elbow joint X-ray images from the same demographic and age group were col-lected and used as an external test set.Model performance was evaluated by comparing the mean ab-solute error(MAE),root mean square error(RMSE),accuracies within±0.7 years(P±0.7 years)and±1.0 years(P±1.0 years)between the estimated age and the actual age,and by drawing radar charts,scat-ter plots,and heatmaps.Results When segmented with Scheme 3,the UNet++model achieved good segmentation performance with a segmentation loss of 0.000 4 and an accuracy of 93.8%at a learning rate of 0.000 1.In the internal test set,the DenseNet121 model with Scheme 3 yielded the best results with MAE,P±0.7 years and P±1.0 years being 0.83 years,70.03%,and 84.30%,respectively.In the external test set,the DenseNet121 model with Scheme 3 also performed best,with an average MAE of 0.89 years and an average RMSE of 1.00 years.Conclusion When performing automatic bone age estima-tion using elbow joint X-ray images in Chinese Han adolescents and children,it is recommended to use the UNet++model for segmentation.The DenseNet121 model with Scheme 3 achieves optimal per-formance.Using segmentation networks,especially that trained with annotation areas encompassing the full elbow joint including the distal humerus,proximal radius,and proximal ulna,can improve the ac-curacy of bone age estimation based on elbow joint X-ray images.
5.Dual-Channel Shoulder Joint X-ray Bone Age Estimation in Chinese Han Ado-lescents Based on the Fusion of Segmentation Labels and Original Images
Hui-Ming ZHOU ; Dan-Yang LI ; Lei WAN ; Tai-Ang LIU ; Yuan-Zhe LI ; Mao-Wen WANG ; Ya-Hui WANG
Journal of Forensic Medicine 2025;41(3):208-216
Objective To explore a deep learning network model suitable for bone age estimation using shoulder joint X-ray images in Chinese Han adolescents.Methods A retrospective collection of 1 286 shoulder joint X-ray images of Chinese Han adolescents aged 12.0 to<18.0 years(708 males and 578 females)was conducted.Using random sampling,approximately 80%of the samples(1 032 cases)were selected as the training and validation sets for model learning,selection and optimization,and the other 20%samples(254 cases)were used as the test set to evaluate the model's generalization ability.The original single-channel shoulder joint X-ray images and dual-channel inputs combining original images with segmentation labels(manually annotated shoulder joint regions multiplied pixel-by-pixel with original images,followed by segmentation via the U-Net++network to retain only key shoulder joint region information)were respectively input into four network models,namely VGG16,ResNet18,ResNet50 and DenseNet121 for bone age estimation.Additionally,manual bone age estimation was con-ducted on the test set data,and the results were compared with the four network models.The mean absolute error(MAE),root mean square error(RMSE),coefficient of determination(R2),and Pear-son correlation coefficient(PCC)were used as main evaluation indicators.Results In the test set,the bone age estimation results of the four models with dual-channel input of shoulder joint X-ray images outperformed those with single-channel input in all four evaluation indicators.Among them,DenseNet121 with dual-channel input achieved best results with MAE of 0.54 years,RMSE of 0.82 years,R2 of 0.76,and PCC(r)of 0.88.Manual estimation yielded an MAE of 0.82 years,ranking second only to dual-channel DenseNet121.Conclusion The DenseNet121 model with dual-channel input combined with original images and segmentation labels is superior to manual evaluation results,and can effectively estimate the bone age of Chinese Han adolescents.
6.Analysis of iodine nutrition status of pregnant women in Zhejiang Province from 2016 to 2021
Guangming MAO ; Zhe MO ; Simeng GU ; Yuanyang WANG ; Fanjia GUO ; Yujie JIANG ; Yahui LI ; Xueqing LI ; Zhijian CHEN ; Xiaofeng WANG ; Xiaoming LOU ; Chenyang LIU
Chinese Journal of Endemiology 2025;44(3):221-226
Objective:To investigate the iodine nutrition status of pregnant women in Zhejiang Province, explore the impact of salt industry system reform on iodine nutrition level of pregnant women, and provide scientific basis for prevention and treatment of iodine deficiency disorders.Methods:From 2016 to 2021, a multi-stage stratified sampling method was used to select 100 pregnant women from 90 counties (cities, districts) in Zhejiang Province each year as survey subjects. Salt samples were collected from pregnant women's families, and one random urine sample was taken for salt iodine and urinary iodine level testing, respectively.Results:A total of 56 581 samples of household edible salt were collected from pregnant women, with a median salt iodine level of 23.20 mg/kg. Among them, 7 961 were non iodized salt, 45 803 were qualified iodized salt, and 2 817 were unqualified iodized salt. The iodized salt coverage rate was 85.93% (48 620/56 581), and the qualified iodized salt consumption rate was 80.95% (45 803/56 581). The proportion of non iodized salt increased from 10.05% (897/8 928) in 2016 to 15.09% (1 461/9 679) in 2021 (χ 2trend = 95.16, P < 0.001). A total of 56 581 urine samples were collected from pregnant women, with a median urinary iodine level of 130.50 μg/L. Among them, the proportions of urinary iodine levels < 150, 150 - 249, 250 - 499, and ≥500 μg/L were 58.32% (32 996/56 581), 27.24% (15 410/56 581), 12.24% (6 926/56 581), and 2.21% (1 249/56 581), respectively. The median urinary iodine level of pregnant women in inland areas was significantly higher than that in coastal areas ( Z = 19.15, P < 0.001). Furthermore, urinary iodine levels exhibited a non-linear decline as age increased (χ 2regression = 12.65, P < 0.001; χ 2partial = 22.65, P < 0.001) and as pregnancy progressed (χ 2regression = 37.28, P < 0.001; χ 2partial = 18.89, P < 0.001). Conclusions:The overall iodine nutrition status of pregnant women in Zhejiang Province is in a state of iodine deficiency (< 150 μg/L), and there is a greater risk in coastal areas compared to inland areas. However, in the context of the reform of the salt industry system, it is still necessary to strengthen the quality supervision of iodized salt, provide scientific iodine supplementation education, promote specialized iodized salt for pregnant women, and strengthen interventions for prevention and control of iodine deficiency disorders.
7.Diagnosis and treatment guideline for acute cervical spinal cord injury without fracture-dislocation in adults (version 2025)
Qingde WANG ; Tongwei CHU ; Jian DONG ; Liangjie DU ; Haoyu FENG ; Shunwu FAN ; Shiqing FENG ; Yanzheng GAO ; Yong HAI ; Da HE ; Dianming JIANG ; Jianyuan JIANG ; Bin LIN ; Bin LIU ; Baoge LIU ; Fang LI ; Feng LI ; Li LI ; Weishi LI ; Fangcai LI ; Xiaoguang LIU ; Hongjian LIU ; Yong LIU ; Zhongjun LIU ; Shibao LU ; Xuhua LU ; Keya MAO ; Xuexiao MA ; Yong QIU ; Limin RONG ; Jun SHU ; Yueming SONG ; Tiansheng SUN ; Yan WANG ; Zhe WANG ; Zheng WANG ; Bing WANG ; Linfeng WANG ; Yu WANG ; Qinghe WANG ; Jigong WU ; Hong XIA ; Guoyong YIN ; Jinglong YAN ; Wen YUAN ; Yong YANG ; Qiang YANG ; Cao YANG ; Jie ZHAO ; Jianguo ZHANG ; Yue ZHU ; Zezhang ZHU ; Yingjie ZHOU ; Zhongmin ZHANG ; Yan ZENG ; Dingjun HAO ; Baorong HE ; Wei MEI
Chinese Journal of Trauma 2025;41(3):243-252
Cervical spinal cord injury without fracture-dislocation (CSCIWFD) is referred to as a special type of cervical spinal cord injury characterized by traumatic spinal cord dysfunction and no significant bony structural abnormalities on imagines. Duo to the high risk of missed diagnosis during the initial consultation, CSCIWFD may lead to progressive neurological deterioration or even complete paralysis, severely impacting patients′ prognosis. Currently, there are no established consensuses over the diagnosis and treatment of CSCIWFD, such as the lack of evidence-based standards for indications of non-surgical treatment and risk of secondary neurological injury, as well as debates over the optimal timing for surgical intervention and indications for different surgical approaches. To address these issues, the Spine Trauma Group of the Orthopedic Branch of the Chinese Medical Doctor Association organized experts in the relevant fields to formulate Diagnosis and treatment guideline for acute cervical spinal cord injury without fracture- dislocation in adults ( version 2025) . Based on evidence-based medicine and the principles of scientific rigor and clinical applicability, the guidelines proposed 11 recommendations covering terminology, diagnosis, evaluation treatment, and rehabilitation, etc., aiming to standardize the management of CSCIWFD.
8.Iodine nutrition status and influencing factors of children and adolescents in Zhejiang Province in 2022
Guangming MAO ; Jiaxin HE ; Zhe MO ; Simeng GU ; Fanjia GUO ; Sujun YAN ; Xinhan ZHANG ; Yuanyang WANG ; Yahui LI ; Zhijian CHEN ; Xiaofeng WANG ; Xiaoming LOU ; Chenyang LIU
Chinese Journal of Endemiology 2025;44(6):451-457
Objective:To analyze the iodine nutrition status of children and adolescents and influencing factors in Zhejiang Province, providing scientific basis for optimizing iodine deficiency disorders (IDD) prevention and control strategies.Methods:In June 2022, a multistage stratified sampling method was used to divide 16 counties (cities, districts, abbreviated as counties) in Zhejiang Province into three categories based on their geographical locations (average distance from the coastline): coastal areas (including Dinghai District, Jiaojiang District, Sanmen County, Cixi City and Lucheng District), sub-coastal areas (including Wuxing District, Haining City, Linping District, Fuyang District and Fenghua District), and inland areas(including Suichang County, Changshan County, Shengzhou City, Jindong District, Dongyang City and Yongjia County). One county was selected from each category, and one township (street) was selected from each county. Two administrative villages (neighborhood committees) were selected from each township (street). Ten households including all children and adolescents aged 6-17 in each household were selected from each administrative village (neighborhood committee). Demographic information and personal dietary characteristics were collected via questionnaires, while household salt and a random urine sample were tested for iodine level. Trend analysis was conducted using a χ 2trend test, and a multivariate logistic stepwise regression model was used to analyze the influencing factors of urinary iodine levels. Results:A total of 755 children and adolescents aged 6-17 were selected, including 387 males (51.26%) and 368 females (48.74%), with an age of (11.24 ± 3.32) years. There were 269 children and adolescents in coastal areas (35.63%) and 409 children and adolescents in urban areas (54.17%). A total of 755 household salt samples were collected, with a median salt iodine concentration of 21.80 mg/kg. These included 263 non-iodized salt samples, 38 unqualified iodized salt samples, and 454 qualified iodized salt samples. The coverage rate of iodized salt was 65.17% (492/755), and the consumption rate of qualified iodized salt was 60.13% (454/755). The distribution of salt iodine quality among children and adolescents in different geographical locations showed statistically significant differences (χ 2 = 111.95, P < 0.001), with the proportion of non-iodized salt gradually decreasing from coastal areas to inland areas (χ 2trend = 90.17, P < 0.001). A total of 755 urine samples were collected, with a median urinary iodine concentration of 186.60 μg/L. The proportions of urinary iodine < 100, 100-199, 200-299, and ≥300 μg/L were 16.95% (128/755), 37.62% (284/755), 24.37% (184/755), and 21.06% (159/755), respectively. The χ 2trend test revealed a nonlinear positive correlation between salt iodine level and urinary iodine level (χ 2regression = 21.98, P < 0.001; χ 2partial = 6.96, P < 0.001). The frequency distribution of urinary iodine in children and adolescents from different geographical locations and between urban and rural areas showed statistically significant differences (χ 2 = 29.63, 16.56, P < 0.001). Among them, the proportion of children and adolescents with urinary iodine < 100 μg/L gradually decreasing from coastal areas to inland areas (χ 2trend = 6.15, P = 0.013). The results of multivariate logistic regression analysis revealed that sub-coastal regions, inland regions, and urban-rural regions ( OR = 1.57, 1.53, 1.64, 95% CI: 1.11-2.24, 1.03-2.27, 1.17-2.32, P < 0.05) were significantly associated with urinary iodine levels in children and adolescents aged 6-17. Conclusions:In 2022, the iodine nutrition of children and adolescents in Zhejiang Province is generally suitable, but there is a risk of iodine deficiency among coastal children and adolescents. Geographic location and urban/rural areas are influencing factors on iodine nutrition status of children and adolescents in Zhejiang Province.
9.The Oretical Study on the Structure and Operation of the Pharmacovigilance System in Group Companies
Yu MAO ; Zhe HUANG ; Wei ZHANG ; Xinghua CHE ; Hong GUO ; Wei ZHANG ; Jian GONG
Herald of Medicine 2025;44(12):2062-2068
The implementation of the Good Pharmacovigilance Practice(GVP)in 2021 has laid a solid foundation for improving China's pharmacovigilance system,a matter of paramount importance currently emphasized by Marketing Authorization Holders(MAHs).Given the unique organizational structures of corporate groups,establishing a centralized pharmacovigilance system can optimize resource utilization.This paper analyzes the challenges faced by corporate groups in developing such central-ized systems and proposes an organizational framework with defined operational divisions.The findings aim to provide actionable insights for vaccine manufacturers in establishing and refining life cycle pharmacovigilance systems.
10.Iodine nutrition status and influencing factors of children and adolescents in Zhejiang Province in 2022
Guangming MAO ; Jiaxin HE ; Zhe MO ; Simeng GU ; Fanjia GUO ; Sujun YAN ; Xinhan ZHANG ; Yuanyang WANG ; Yahui LI ; Zhijian CHEN ; Xiaofeng WANG ; Xiaoming LOU ; Chenyang LIU
Chinese Journal of Endemiology 2025;44(6):451-457
Objective:To analyze the iodine nutrition status of children and adolescents and influencing factors in Zhejiang Province, providing scientific basis for optimizing iodine deficiency disorders (IDD) prevention and control strategies.Methods:In June 2022, a multistage stratified sampling method was used to divide 16 counties (cities, districts, abbreviated as counties) in Zhejiang Province into three categories based on their geographical locations (average distance from the coastline): coastal areas (including Dinghai District, Jiaojiang District, Sanmen County, Cixi City and Lucheng District), sub-coastal areas (including Wuxing District, Haining City, Linping District, Fuyang District and Fenghua District), and inland areas(including Suichang County, Changshan County, Shengzhou City, Jindong District, Dongyang City and Yongjia County). One county was selected from each category, and one township (street) was selected from each county. Two administrative villages (neighborhood committees) were selected from each township (street). Ten households including all children and adolescents aged 6-17 in each household were selected from each administrative village (neighborhood committee). Demographic information and personal dietary characteristics were collected via questionnaires, while household salt and a random urine sample were tested for iodine level. Trend analysis was conducted using a χ 2trend test, and a multivariate logistic stepwise regression model was used to analyze the influencing factors of urinary iodine levels. Results:A total of 755 children and adolescents aged 6-17 were selected, including 387 males (51.26%) and 368 females (48.74%), with an age of (11.24 ± 3.32) years. There were 269 children and adolescents in coastal areas (35.63%) and 409 children and adolescents in urban areas (54.17%). A total of 755 household salt samples were collected, with a median salt iodine concentration of 21.80 mg/kg. These included 263 non-iodized salt samples, 38 unqualified iodized salt samples, and 454 qualified iodized salt samples. The coverage rate of iodized salt was 65.17% (492/755), and the consumption rate of qualified iodized salt was 60.13% (454/755). The distribution of salt iodine quality among children and adolescents in different geographical locations showed statistically significant differences (χ 2 = 111.95, P < 0.001), with the proportion of non-iodized salt gradually decreasing from coastal areas to inland areas (χ 2trend = 90.17, P < 0.001). A total of 755 urine samples were collected, with a median urinary iodine concentration of 186.60 μg/L. The proportions of urinary iodine < 100, 100-199, 200-299, and ≥300 μg/L were 16.95% (128/755), 37.62% (284/755), 24.37% (184/755), and 21.06% (159/755), respectively. The χ 2trend test revealed a nonlinear positive correlation between salt iodine level and urinary iodine level (χ 2regression = 21.98, P < 0.001; χ 2partial = 6.96, P < 0.001). The frequency distribution of urinary iodine in children and adolescents from different geographical locations and between urban and rural areas showed statistically significant differences (χ 2 = 29.63, 16.56, P < 0.001). Among them, the proportion of children and adolescents with urinary iodine < 100 μg/L gradually decreasing from coastal areas to inland areas (χ 2trend = 6.15, P = 0.013). The results of multivariate logistic regression analysis revealed that sub-coastal regions, inland regions, and urban-rural regions ( OR = 1.57, 1.53, 1.64, 95% CI: 1.11-2.24, 1.03-2.27, 1.17-2.32, P < 0.05) were significantly associated with urinary iodine levels in children and adolescents aged 6-17. Conclusions:In 2022, the iodine nutrition of children and adolescents in Zhejiang Province is generally suitable, but there is a risk of iodine deficiency among coastal children and adolescents. Geographic location and urban/rural areas are influencing factors on iodine nutrition status of children and adolescents in Zhejiang Province.

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