Purpose: An analysis model based on monthly or fortnight data is inadequate to precisely evaluate the impact of media reporting of suicide on suicide rates as well as the time lag from exposure to the report of a suicide. Thus, we used daily time-series data and examined the association between newspaper articles on suicide and suicide attempts in Japan.
Methods: The Box-Jenkins transfer function model was applied to daily time-series data for the period March 27-May 21, 2008.
Results: Newspaper articles on suicide using hydrogen sulfide at (t - 1) were related to suicide attempts at (t) (ps < 0.001 and 0.05). Newspaper articles on suicides using hydrogen sulfide on the front page at (t - 1) were related to suicide attempts at (t) (p < 0.00). The magnitude of the impact of newspaper articles about suicide at (t - 1) or (t - 3) on "copy-cat" suicide attempts became greater as the number of news articles violating the media suicide recommendations increased.
Conclusions: The time lag between exposure to newspaper reports of suicide and attempts was 1 or 3 days, and the magnitude of the impact of front page articles was about four times as great as that of suicide articles in general.