Risk factors associated with borderline intelligence in schoolchildren: a case-control study

To determine risk factors associated with borderline intelligence during intra-uterine life, delivery and the neonatal periods. In a case-control study, 200 school children in first grade, age six years were recruited. A standard intelligence quotient [IQ] test was used for psychometric testing. Cases had a borderline intelligence [70 to 84 score] and normal controls had an IQ of 85 or above scores. Cases and controls were matched for gender. Regression analysis showed that mother's illiteracy [Adjusted OR=2.7, 95% Cl, 1.6-4.2, p=0.001], familial history of mental retardation [AOR=2.1, 95% Cl, 1.4-3.5, p=0.002] and maternal drug consumption during pregnancy [AOR=1.7, 95% Cl, 1.1-2.5, p=0.003] were the main adjusted risk factors associated with borderline intelligence in childhood. No significant association was found between adverse birth outcomes including low birth weight and prematurity and borderline intelligence in children. Intelligence quotient [IQ] of schoolchildren is affected by both prenatal and postnatal factors as well as social determinants such as parental education. Controlling these factors has important implications for preventive strategies in psychological, maternal and child health programs worldwide