A new life-span approach to conscientiousness and health: combining the pieces of the causal puzzle

Abstract

Conscientiousness has been shown to predict healthy behaviors, healthy social relationships, and physical health and longevity. The causal links, however, are complex and not well elaborated. Many extant studies have used comparable measures for conscientiousness, and a systematic endeavor to build cross-study analyses for conscientiousness and health now seems feasible. Of particular interest are efforts to construct new, more comprehensive causal models by linking findings and combining data from existing studies of different cohorts. Although methodological perils can threaten such integration, such efforts offer an early opportunity to enliven a life course perspective on conscientiousness, to see whether component facets of conscientiousness remain related to each other and to relevant mediators across broad spans of time, and to bolster the findings of the few long-term longitudinal studies of the dynamics of personality and health. A promising approach to testing new models involves pooling data from extant studies as an efficient and heuristic prelude to large-scale testing of interventions.

Figure 1

Lifespan mediation model (partial), in which conscientiousness influences the health-related behaviors that a person engages in, which in turn predict length of life. In the lifespan model, conscientiousness is measured prior to and simultaneously with the mechanism (behavior), which is measured prior to the health outcome (length of life). C = conscientiousness; Behavior = health-relevant behaviors; dotted lines indicate implicit but unmeasured variables and processes.

Figure 2

The ultimate goal of collaborative lifespan studies and integrative analyses is to test full causal models. In this example, biological elements and early personality influence personality and health processes throughout life. Personality impacts the behaviors people engage in, the relationships people have, and the situations they select. Conscientiousness and social relationships also moderate stressful experiences that occur. To sort out the various influences, variables necessarily need to be measured prospectively and repeatedly across long periods of life, or carefully combined from relevant overlapping studies. The “Biological Base” includes genes, the impact of the prenatal environment (e.g., mother’s alcohol or drug use during pregnancy), and the central nervous system changes in the early post-natal environment. Figure 2 is an example, not a complete model. C = conscientiousness; Behavior = health-relevant behaviors such as smoking.