Analyses comparing those who have already participated in the teen follow-up and those not tested identified no group differences in maternal age at the time of conception, caregiver education, IQ, or SES, child gender, or prenatal drug or alcohol exposures. The only difference was found in marital status: caregivers who were married at the age 7-year assessment were less likely to participate at the age 14-year follow-up than caregivers who were not married at the age 7 assessment (F=5.5, df=1, p=0.019).
