The administrative prevalence of mental retardation in 10-year-old children in metropolitan Atlanta, 1985 through 1987

Objectives. In this study, data from the Metropolitan Atlanta Developmental Disabilities Study were used to determine the administrative prevalence (i.e., the number of children previously identified for service provision) of mental retardation among 10-year-old children during the years 1985 through 1987. Methods. Children with mental retardation (intelligence quotient [IQ] of 70 or lower) were identified by review of records from multiple sources, with the public schools as the primary source. Results. The overall administrative prevalence of mental retardation was 12.0 per 1000 children. The rate for mild mental retardation (IQ of 50 to 70) was 8.4 per 1000 and the rate for severe mental retardation (IQ lower than 50) was 3.6 per 1000. The prevalence was higher in Black children than in White children (prevalence odds ratio [POR] = 2.7) and in boys than in girls (POR = 1.4). Children with severe mental retardation had more coexisting disabilities than did children with mild mental retardation. Conclusions. The mental retardation prevalence rates reported here, especially the race-specific rates, may reflect social and demographic features unique to the metropolitan Atlanta area and therefore should be used with caution in making comparisons with other populations.