to chi-square analyses, there were no differences between those who maintained participation and those who were lost to attrition on the basis of the sex of the child; mother-, father-, or teacher-reported problem behavior grouping; or type of household (single parent, two parent, or extended family). Whites appeared somewhat more likely to remain in the study than those of other ethnicities, χ2(5, N = 213) = 13.17, p < .05. Moreover, the 58 children who did not come to the laboratory at T3 were lower in T1 observed persistence than those who came to the laboratory at T3, t(210) = −2.96, p < .01.
