Methods: Participants from the Fast Track normative and control groups (n = 753, 58% male, 46% African Americans) annually reported parental warmth and consistent discipline from kindergarten to grade 5. Teachers reported child social competence in grade 6. Parents reported child internalizing problems in grade 7. Children reported their substance use (a composite score of past year drunkenness, lifetime marijuana use, and current tobacco use) in grade 7. Sex, age, cohort, initial risk for externalizing problems in kindergarten, SES, and ethnicity were included as covariates. Parental lability was constructed as the standard deviation of within-person residuals around developmental trajectories not explained by intercept and linear slopes as modeled in latent growth curve models (Lippold et al., 2016).
Results: Parenting lability in both warmth and consistent discipline negatively predicted social competence (βs = -0.09 and -0.11, respectively, ps = .045 and .016). Parenting lability in warmth also positively predicted internalizing problems (β = 0.11, p = .023), whereas for consistent discipline only its intercept was negatively associated with internalizing problems (β = -0.18, p = .041). Neither parenting lability predicted the substance use composite in grade 7. However, intercept and slope of consistent discipline were both negatively associated with substance use (ORs = 0.42 and 0.00, respectively, ps = .023 and .002).
Conclusions: The findings demonstrate that parenting lability in parental warmth and consistent discipline is associated with child social competence and internalizing problems, highlighting the importance of consistent and reliable parenting practices throughout childhood. Family-focused parenting intervention programs should also emphasize this aspect of parenting in their training sessions for better effectiveness.