Integrating prospective longitudinal data: modeling personality and health in the Terman Life Cycle and Hawaii Longitudinal Studies

Abstract

The present study used a collaborative framework to integrate 2 long-term prospective studies: the Terman Life Cycle Study and the Hawaii Personality and Health Longitudinal Study. Within a 5-factor personality-trait framework, teacher assessments of child personality were rationally and empirically aligned to establish similar factor structures across samples. Comparable items related to adult self-rated health, education, and alcohol use were harmonized, and data were pooled on harmonized items. A structural model was estimated as a multigroup analysis. Harmonized child personality factors were then used to examine markers of physiological dysfunction in the Hawaii sample and mortality risk in the Terman sample. Harmonized conscientiousness predicted less physiological dysfunction in the Hawaii sample and lower mortality risk in the Terman sample. These results illustrate how collaborative, integrative work with multiple samples offers the exciting possibility that samples from different cohorts and ages can be linked together to directly test life span theories of personality and health.

Figure 1

Conceptual model. In this model, child personality traits predict adult health, partially mediated through educational attainment and health behaviors (for simplicity, we focus in this paper on alcohol abuse, but other behaviors could be included).

Figure 2

Final child personality (average age 10) measurement model in the Terman Sample. See Appendix for traits and descriptions. Standardized path estimates are presented. Emotional stability was evaluated as a single observed variable. Model was estimated in R (version 2.15.0, package lavaan).

Figure 3

Final child personality (grades 1, 2, 5, or 6) measurement model in the Hawaii sample. See Appendix for traits and descriptions. ^* indicates reversed-scored items. Standardized path estimates are presented. Model was estimated in R (version 2.15.0, package lavaan).

Figure 4

Final estimated SEM model for the combined sample (N = 2,255, n_Terman = 1085, n_Hawaii = 1170), with the child (age 10–11) personality composite factor variables predicting midlife (~ age 50) health via education and alcohol abuse (~ age 40). Standardized estimates are given for the significant pathways, shown as solid lines (dotted lines were non-significant). The model was estimated as a multi-group model in R (version 2.15.0, package lavaan), with paths and loadings unconstrained across groups, allowing a direct comparison of sample heterogeneity.