Association of temporal factors and suicides in the United States, 2000-2004.
OBJECTIVE
The purpose of the study was to examine the association of temporal factors, in particular days of the week and seasons of the year and death from suicide in the United States.


METHODS
Data were pooled from the Multiple Cause of Death Files. Hierarchical logistic regression models were fitted to all deaths occurring in 2000 through 2004 by suicide.


RESULTS
The incidence of suicide was significantly higher on Wednesdays, compared to Sunday. Specifically, individuals were 99% more likely to kill themselves on Wednesday than on Sunday. Suicides were more prevalent in the summer months, and they were less likely to occur in winter. The state suicide rate significantly elevated individual suicide risk. The results held even after controlling for the potentially confounding effects of socio-economic and demographic variables at both the individual and state levels.


CONCLUSIONS
It was concluded that the observed association between seasonality and suicide cannot be discounted as a mere coincidence. Future research ought to focus on integrating individual level data and contextual variables when testing for seasonality effects.
Kposowa
Augustine J
AJ
Department of Sociology, University of California, Riverside, CA 92521, USA. augustine.kposowa@ucr.edu
D'Auria
Stephanie
S
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D016022:Case-Control Studies; D002423:Cause of Death; D003644:Death Certificates; D005006:Ethnicity / Q000523:psychology / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D038801:International Classification of Diseases; D016015:Logistic Models; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D012621:Seasons; D012737:Sex Factors; D013405:Suicide / Q000208:ethnology / Q000523:psychology / Q000706:statistics & numerical data*; D014481:United States / Q000453:epidemiology