JMIR Publications

ABSTRACT

Background:

To better understand domestic violence, data sources from multiple sectors such as police, justice, health, and welfare are needed. Linking police data to databases from other agencies could provide unique insights and promote an all-of-government response to domestic violence. The New South Wales Police Force attends domestic violence events and records information in the form of both structured data and a free text narrative, with the latter shown to be a rich source of information.

Objective:

To examine the concordance (i.e., matching) between mental illness mentions extracted from the police’s event narratives with mental health diagnoses from hospital and emergency department records.

Methods:

Using different window periods (one/three/six/twelve months) before and after a domestic violence event, we automatically linked data from 416,441 police event narratives between December 2005 and January 2016 to clinical records from the Emergency Department Data Collection and the Admitted Patient Data Collection in New South Wales, Australia.

Results:

Using a two-year (i.e., twelve months before and after) window period, <1% (3,020) of events had a mental illness mention and a corresponding hospital record. 16% of domestic violence events for both persons of interest (POIs) (382 out of 2,395) and victims (101 out of 631) had agreement between hospital records and police narrative mentions of mental illness. 51,025 (12.2%) events for POIs and 14,802 (3.5%) events for victims had mental illness mentions in their narratives but no hospital record. Only 841 events for POIs and 919 events for victims had a hospital record within 48 hours of the DV event.

Conclusions:

Our findings reinforce the view that surveillance systems based solely on hospital presentations are very limited in terms of coverage, with hospitals seeing only a fraction of mental illness conditions arising from domestic violence situations. This demonstrates that police appear to have substantial visibility of mental illness in domestic violence covering scope and the severity of conditions. While the police data come with their own set of limitations, the coverage of mental health within domestic violence police narratives highlights the need to be able to link various data sources for large scale surveillance and reporting that could prove beneficial for vulnerable populations.