The correlation between maltreatment and conduct problems was small, and the bivariate analyses lacked power to reliably distinguish common genetic factors from common shared environmental factors mediating this correlation. Therefore, the present results must be interpreted cautiously. Several factors may contribute to this lack of power. Participants reported at different times about maltreatment and conduct problems they experienced at different periods of their life. Maltreatment may have been assessed unreliably because it was reported retrospectively, only four items were used, and respondents were required to define whether they were able to be left alone, what constitutes a basic need, and whether an experience was sexual. The physical maltreatment item captured relatively mild maltreatment and corporal punishment, which may minimize its relationship with conduct problems. Although this study included approximately 4,000 participants, only 81% of those who completed items about conduct problems (Waves I & II) also completed maltreatment items (Wave III), and those who did not complete wave III had slightly more conduct problem symptoms than those who did, as incarcerated individuals were not assessed at wave III (Haberstick et al. 2005). Further, many participants did not endorse any maltreatment or conduct problems.
