Weekly lottery sales volume and suicide numbers: a time series analysis on national data from Taiwan

To investigate the association between weekly lottery sales and number of suicide deaths in Taiwan.

All suicides aged 15+ years during 2004–2006 in Taiwan were included. Poisson autoregression time series models investigated
associations of weekly numbers with contemporaneous and recent sales from two national lotteries in operation. Adjustments
were made for seasonal fluctuation, temperature, monthly unemployment and autocorrelation.

In fully adjusted models, suicide deaths were negatively correlated with sales of tickets for a low-prize, low-cost lottery
system. However, they were correlated positively with recent sales for a higher-cost, larger-prize system. Both correlations
were stronger for male than female suicide numbers but differed in terms of age groups most strongly implicated.

Associations between lottery sales and suicide numbers differed according to the nature of the lottery. A low-prize, low-publicity
system appeared to be more benign than a high-prize, high-publicity one.