The association between the incidence of emergency department attendances for alcohol problems and assault incidents attended by police in New South Wales, Australia, 2003-2008: a time-series analysis.

AIM

To assess the short-term temporal relationship between emergency department (ED) attendances for acute alcohol problems and assaults reported to police.

DESIGN

Cross-sectional time-series analysis.

SETTING

Population of New South Wales (NSW), Australia between 2003 and 2008.

PARTICIPANTS

All patients who attended any of 56 large NSW public hospital EDs and had a recorded diagnosis of acute alcohol problems, and all persons involved in assault incidents reported to the NSW Police Force.

MEASUREMENTS

Weekly count time-series were formed for ED attendances, assault incidents and persons of interest in assault incidents. Cross-correlation analysis was used to determine any time lag in the relationship between the alcohol and the assault series. Poisson regression was used to assess the magnitude of the relationship. Splines of week controlled for seasonality.

FINDINGS

There was no time lag found between the ED and police series. A weekly increase of 100 attendances in people aged 15 years and above to EDs for alcohol problems was associated with an 11% [95% confidence interval (CI): 7-15%] increase in the number of incident assaults attended by police. The relationship was similar and statistically significant for domestic and non-domestic assaults and urban areas. The association was stronger between ED attendances and persons of interest aged 15-24 years (27%, 95% CI: 15-41%), 15-24-year-old males (39%, 95% CI: 16-66%) and 15-24-year-old females (66%, 95% CI: 20-129%).

CONCLUSIONS

There is a clear, short-term temporal association between independent population-level markers of excessive alcohol use and violence.