A population-based cross-sectional study examining homicides among community-dwelling older adults in Victoria, Australia: A study protocol

BACKGROUND: There is a need for both descriptive and analytical evidence on the factors associated with older adult homicide. The current landscape is insufficient because most published research is confined to the United States, and contains insufficient data about the homicide context. This study protocol describes the proposed method for examining the characteristics and factors associated with older adult homicide in the Australian state of Victoria, using data generated for the criminal and coronial investigation into these deaths stored in the Victorian Homicide Register (VHR). Outcomes will support practitioners, policy makers and other key stakeholders to strengthen prevention strategies to reduce the risk of future homicides among older Victorians. METHODS: This study will comprise a single-jurisdiction population-based cross-sectional design to analyse consecutive cases of homicide among community-dwelling older adults in Victoria, Australia for the period 2001 to 2015. All homicides of adults aged 18 years and older, and where the Coroner’s investigation is completed at data extraction will be included. Variables will be selected in accordance with elements of the social-ecological model (i.e., individual, interpersonal, incident, and community). This will include: socio-demographic characteristics; presence of mental or physical illness; deceased-offender relationship; nature of any abuse between the deceased and offender; incident location and weapon used; the presence of alcohol or drugs; and criminal justice outcomes. Homicide rates per 100,000 population will be calculated for older adults (aged 65 years and older) and younger adults (aged 18–64 years), and compared as rate ratios using Poisson regression. Descriptive statistics and cross-tabulation will be generated for factors associated with homicide for older compared to younger adults. Homicide typologies based on deceased-offender relationship and motive will be explored within group and family homicides will be compared between older and younger adults.