Abstract
Constructs representative of global positive expectancies (GPE) such as dispositional optimism and hope have been theoretically and empirically linked to many positive mental and physical health outcomes. However such expectancies’ health implications for adolescents, as well as their trajectory over time, are less well understood than for adult populations. This study tested whether GPE predict the key indicators of adolescents’ future physical health status, their health-related behaviours. A prospective longitudinal study design was employed whereby a diverse population-based cohort (N = 744; mean age at baseline = 12) completed three surveys over approximately 18 months. Rigorous tests of causal predominance and reciprocal effects were conducted through latent growth and cross-panel structural equation models. Results showed GPE systematically decreased during the course of the study, yet higher initial levels of GPE predicted less alcohol drinking, healthier food choice and greater physical activity over time. GPE's protective relationships towards health protective behaviours (vs. health risk behaviours that also included tobacco smoking) appear more independent from depressive symptomatology, and the primary findings were robust across socio-demographic groups.
Acknowledgements
This research was supported by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (HD053590), the National Institute on Alcohol Abuse and Alcoholism (AA12803) and the California Tobacco-Related Disease Research Program (7KT-0151). All data were collected using active parent and active student consent procedures consistent with state of California regulations. The data collection was approved by the federally approved internal review board of ETR Associates (Scotts Valley, CA), and the analyses plan for this study was approved by the internal review board of the University of Arizona. The author thanks the staff of ETR Associates, students and school district officials, and Peter R. Giacobbi, Matthias R. Mehl and Teresa M. Granillo for their helpful comments on the manuscript.