Another study, conducted by Appels et al, investigated the effect of type D behavior on sudden cardiac death. This study involved interviewing the next-of-kin of the sudden cardiac death victims to determine whether they were type D or not. Patients scoring high on negative affectivity and social inhibition (the two dimensions of the type D personality subtype) were found to be seven times more likely to suffer sudden cardiac death. See also Psychology Schizoid personality disorder References Baron, R. A., Earhard, B., & Ozier, M. (2001). Psychology (3rd Canadian ed.). Scarborough, ON: Allyn & Bacon. http://www.health.harvard.edu/press_releases/type_d_personality Personality theories