2005年全国碘缺乏病监测8～10岁儿童智力测定结果分析

目的了解全民食盐加碘10年后8-10岁儿童智力水平。方法以省为单位采用人口比例概率抽样方法(PPS),按省份、年龄、性别和碘营养状况分组,用中国联合型瑞文测验(CRT-C2)方法测定儿童智商(IQ)。结果全民食盐加碘10年后,32个省份的38 448名儿童中,IQ均值为103．4。其中男、女儿童IQ均值分别为103．4和102．0,IQ≤69者占4．4％。实施食盐加碘措施较差的省份,儿童IQ明显低于全国平均值。碘营养适宜时IQ均值最高(103．8),碘不足时儿童IQ均值降低(98．7),碘过量(103．2)与碘适宜比较儿童IQ值未见明显改变。结论碘不足明显影响了8-10岁儿童智力发展,在全国非高碘病区实施食盐加碘防治碘缺乏病策略是正确、有效的;非高碘地区碘过量没有明显影响8-10岁儿童智力发育;近10年来,随着生活水平的提高,全国儿童智力发育水平又有所增长,现有的IQ检测常模有必要再重新修订。

Surveillance on iodine deficiency disorders in China in 2005: an analysis of intelligence test

Objective To study children's intelligence after universal salt iodization (USI) had been implemented for 10 years in China. Methods The children of 8 to 10 years were sampled by population proportion sampling method. The samples were divided into groups according to the province, age, sex, urine iodine. Intelligence quotient (IQ) values were measured by the combined Raven's Test in China (CRT-C2). Results The mean IQ of children was 103.4, being 103.4 and 102.0 respectively for boys and girls after USI had been performed for 10 years in 32 provinces, children with IQ values less than or equal to 69 accounted for 4.4% of the population. Children with IQ lower than the average level distributed in the provinces where the USI was not well implemented. Children with adequate iodine contents had the highest IQ (103.8), and IQ decreased obviously when the children was iodine-deficient (98.7). There was no significant difference of averaged IQ between children with excessive and adequate iodine. Conclusions Iodine deficiency significantly affects intelligence development of children aged 8 -10 years old, indicating that it is correct and effective to implement the strategy of putting iodine into edible salt to control iodine deficiency disorders in non-iodine-excessive endemic areas in China; iodine excess has no obvious influence on intelligent development of the children aged 8-10 years in non-iodine-excessive areas; with the improvement of living quality, developing level of children's intelligence in our country is elevated in the recent decades, so it is necessary to revise the present IQ norm of CRT-C2 .