A case - control study on risk factors of midlevel mental retardation in children, Bandar Abbas, Iran

This study was conducted to determine risk factors of midlevel mental retardation in Bandar Abbas, Iran. Material &

In a case control study 93 cases were compared with similar number of hospital controls. Cases and controls were matched for age group. The Odds Ratio of independent variables (i.e. familial relation between parents, birth interval to later and former children, mother age in delivery, place of delivery, antenatal cares, family history of mental retardation, socio-economic status of family) for developing midlevel mental retardation were estimated. Chi square and logistic regression were performed to analyze data.

Determinant of midlevel mental retardation in this study was "time interval to birth of next child". Estimated Odds Ratio for "less than three year's interval" was 3.5 (95%CI= 1.7-7.0).

Improving family planning programs and child spacing can be suggested to reduce midlevel mental retardation in this region. Further investigations are needed to determine the role of genetic and non-genetic chromosal abnormalities.