Objective: To determine whether initial body mass index for age (zBMI) and internalizing symptoms predict longitudinal changes in zBMI and internalizing symptoms-and the extent to which sex and race moderate these relations.
Methods: Participants included 12,674 (51% male) youth from the Early Childhood Longitudinal Study, Kindergarten Class 1998-1999. Data were collected in kindergarten, 1st, 3rd, 5th, and 8th grades. Teacher-reported internalizing symptoms were measured with the Social Rating Scale.
Results: Internalizing symptoms followed a quadratic growth trajectory, with initial low levels of symptoms that gradually increased over time and eventually leveled. zBMI followed a piecewise growth trajectory, with a transition in slope at 1st grade. Interactions emerged between zBMI and internalizing symptoms for White males.
Conclusions: Associations between internalizing symptoms and BMI begin in early childhood for White males, and changes in zBMI are a function of the interactive effect of initial levels of internalizing difficulties and adiposity status.
Keywords: internalizing trajectories; longitudinal research; parallel process latent growth curve modeling; zBMI trajectories.
© The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: [email protected].