Bivariate analyses
In table 2, we present bivariate analyses of biological and socioeconomic factors with dental caries at each age. Although birth weight and family income were treated as continuous variables in the statistical analyses, we categorised them to illustrate their relationships to dental caries. We observed a gradient by birth weight and parity. The relationship between maternal age at delivery and dental caries drew a U shape. Mothers younger than 25 and older than 35 reported more dental visits than those between 25 and 35.