Invited Commentary:Personality as a Causal Factor in Cancer Risk and Mortality-Time to Retire a Hypothesis?

In this issue of the Journal, Nakaya et al. (Am J Epidemiol. 2010;172(4):377-385) report null findings from a large-scale prospective study of the prognostic value of 2 personality dimensions, neuroticism and extraversion, for cancer risk and mortality. The study stands out because of its exceptionally large sample size and its methodological strengths. The authors discuss the Nakaya et al. study in the context of persistent beliefs about the role of personality in cancer onset and survival despite a pattern of null findings in the literature, as well as the influence of extreme outlier findings from one investigator group that continue to be cited. They question whether it is time for the field to move on from considering a role for personality in cancer to more promising and modifiable factors.