Seasonal variation in suicide and homicide: a question of consistency.

Seasonal or monthly fluctuations in suicides and homicides were analysed using US mortality data for the years 1969-78 using periodic regression analysis. The results were generally consistent (year-to-year) over the 10-year period. The pattern for suicide was distinctly seasonal: it was above average all spring and below average all winter. For homicides the pattern was more monthly with July-September and December being above average times and January-June being below average. (EXCERPT)