Motohashi Y
Department of Public Health and Environmental Science, Faculty of Medicine, Tokyo Medical and Dental University, Japan.
Suicide Life Threat Behav. 1990 Winter;20(4):352-61.
Circadian variations in suicide attempts in Tokyo from 1978 to 1985 were analyzed on the basis of records of the Ambulance Service of Tokyo. A significant circadian variation in suicide attempts was demonstrated by the cosinor method, power spectrum analysis (by the maximum-entropy method), and analysis of variance. The peak time for suicide attempts was established by cosinor analysis as about 1800 hours (6:00 P.M.). The circadian variation in suicide attempts seemed to be associated with endogenous rhythms such as mood, as well as with daily variation in social activities.
