Testing the cohort size hypothesis of suicide and homicide rates in Canada and the United States

Suicide and homicide can be seen as interwoven expressions of lethal violence. Both forms of annihilation result from a combination of negative life events. Easterlin/Holinger suggested that one such event might result from the impact of the size of the cohort on the behavior of its own cohort as well as the behavior of other cohorts. A study of Canada and the United States from 1969 to 1987 indicated that the suicide rates of males aged 20 to 34 were positively associated with their relative cohort size, lending some support to the hypothesis that large cohort sizes result in relative deprivation for young adults. The cohort size hypothesis was not strongly supported by data for homicide and by data for women. A word of caution is provided about the fact that cohort size is measured differently by various researchers, suggesting prudence in comparisons across studies. This study, however, does present data using the most common measures. These results converge with the general findings.