ABSTRACT
BACKGROUND: There are about 20 millions people suffering from mental retardation in China and about 200 thousands newborns of mental retardation are born every year. Mental retardation in children is a result of multiple factors.OBJECTIVE: To explore the popular causes of mental retardation in order to provide scientific evidence for effectively preventing mental retardation.DESIGN: An observational case study taking children with mental retardation as the subjects.SETTING: Population and family plan institute of a hospital.PARTICIPANTS: Totally 1 336 disabled children in 6 counties of Tai' an city diagnosed by family planning authority from January 1998 to December 2001 were selected. Inclusive criteria: intelligence quotient(IQ) < 55 and met the condition of disabled children, aged over 4 years old, those whose parents requested to give birth to the second baby due to mental retardation of the first children. Exclusive criteria: Disabled children with diseases of other systems. A total of 613 disabled kids met the above standards, aged from 4 to 14 years old, including 509 boys and 104 girls with the ratio of boy to girl of 4.9 to 1.INTERVENTIONS: All the children with mental retardation were examined by professional pediatrists and experts of family planning medical appraisal and conducted IQ test by using Chinese Wechsler Intelligence Scale for Children(C-WISC). Uniform survey was made according to all the data and processed by SPSS10. 0.MAIN OUTCOME MEASURES: The main factors caused mental retardation in kids.RESULTS: Among the 1 336 disabled kids in Tai' an city, the incidence rate of mental retardation was 45.88%. There were 112 mild cases and 501 severe cases with mental retardation among the 613 disabled kids. The component ratio of etiological classification on prenatal, perinatal and postnatal factors was 36.7%, 29.85% and 13.21% respectively, and 20. 23% of them were caused by unclear reasons.CONCLUSION: It is the key mean to prevent the occurrence of mental retardation by reinforcing maternal health, improving obstetric quality, preventing acquired disease and paying attention to early education.