为了解江苏省0～6岁儿童智力残疾的患病率及其影响因素,我们采用回顾性调查方法进行了研究。对象　根据最小可分析残疾病例数,确定本次调查样本量为2001年6月1日零时以前出生0～6岁儿童,城乡各5000名。采用三阶段、分层、整群随机抽样的方法,首先按最近的经济指标(国民生产 To understand the prevalence of mental retardation among children aged 0 ~ 6 in Jiangsu Province and its influential factors, we conducted a retrospective survey. Subjects According to the minimum number of cases of disability can be analyzed, the sample size of this survey is determined to be children aged 0-6 years old before the zero hour on June 1, 2001, and 5,000 in urban and rural areas respectively. Using three stages, stratified, cluster random sampling method, first according to the most recent economic indicators (National Production