Bollen K A
Demography. 1983 Feb;20(1):45-59.
Among the various types of mortality, motor vehicle fatalities (MVF) and suicides are two that are very responsive to social, economic, and psychological factors. The analysis of the temporal patterns of suicides and MVF points to important but neglected forces affecting them. This paper examines the daily patterns of MVF and suicides for the United States from 1972 to 1976. The effects of the day of the week, month, year, and holidays on these types of mortality are estimated. Total MVF and suicides, as well as daily differentials by sex, age, and race, are analyzed with regression techniques. The results show that temporal variations are stronger in MVF than in suicides but are present in both. MVF tend to peak on Saturday, in the summer months, in 1972 and 1973, and on holidays. Suicides are generally highest on Monday, in the spring months, in 1975 and 1976, and on nonholidays. Differentials in the temporal patterns are evident. For instance, whites generally have a sharper decline in suicides on holidays than do nonwhites. The holiday peak in MVF for the 60 and over population is Christmas, while it is New Year's for the younger age groups. Males exhibit a greater increase in suicides from March to May than do females. Finally, the results of a comparison of the daily patterns of MVF and suicides revealed a negative correlation. This contrasted with the strong positive relationship between MVF and suicides generally found in cross-sectional studies. The implications of these findings are briefly discussed.
在各类死亡类型中，机动车致死（MVF）和自杀是对社会、经济及心理因素非常敏感的两类。对自杀和机动车致死的时间模式分析揭示了影响它们的重要但被忽视的因素。本文研究了1972年至1976年美国机动车致死和自杀的每日模式。估计了一周中的日期、月份、年份和节假日对这些死亡类型的影响。运用回归技术分析了机动车致死和自杀的总数，以及按性别、年龄和种族划分的每日差异。结果表明，机动车致死的时间变化比自杀更强烈，但两者都存在时间变化。机动车致死往往在周六、夏季月份、1972年和1973年以及节假日达到峰值。自杀通常在周一、春季月份、1975年和1976年以及非节假日达到最高值。时间模式上的差异很明显。例如，白人在节假日的自杀率下降幅度通常比非白人更大。60岁及以上人群机动车致死的节假日峰值是圣诞节，而较年轻年龄组的峰值是新年。男性从3月到5月的自杀率增幅比女性更大。最后，机动车致死和自杀每日模式的比较结果显示出负相关。这与横断面研究中通常发现的机动车致死和自杀之间的强正相关形成对比。简要讨论了这些发现的意义。
