Abstract
The socioeconomic (SES) gradient in health whereby higher position equates to better health spans both time and place and is found for almost all diseases and many health risk behaviours. The near universality of this phenomenon has led to a search for more fundamental causes. Although differences in material resources and/or psychosocial attributes have been postulated, neither can satisfactorily explain the ubiquity of the socioeconomic-health gradient. In this edition of the journal, Pulkki and colleagues ask if adolescent personality traits can explain the inverse relation between selected cardiovascular health risk behaviours and educational achievement. Their longitudinal study shows that a set of "Type A" - like personality traits predict educational attainment (a component of SES) and accounts for part of the SES gradient in health risk behaviour. The study delivers an important message that we hope will not be lost in the details of the work. The message, as we understand it, is that collaboration between epidemiologists and personality psychologists may prove helpful in better understanding how one’s position in the social structure affects health. In this commentary, we amplify two issues. First, we discuss promising directions in the measurement of personality, and the need to use more comprehensive, and more comparable, personality measurement across epidemiological studies. Second, we discuss issues of causation, and identify alternative ways in which personality may contribute to the social gradient in health.