Investigators

Reece Cossar


Supervisors

Professor Paul Dietze, Professor Mark Stoové


Background

People with severe mental illness are at a higher risk of problematic substance use. Dual diagnosis – a term used to describe the co-occurrence of substance dependence with one or more psychiatric disorders – compounds the independent impact of drug dependence and mental health problems and is widely documented in prison studies. Prevalence of dual diagnosis among populations involved in the criminal justice system varies and dependent on sampling methodology – yet it has been estimated as high as 92 per cent in forensic mental health services.

Understanding and explaining both individual and group offending patterns are primary aims of developmental and life-course criminology. As such, mapping patterns of crime for people with histories of injecting drug use and those with dual diagnosis may assist in identifying key periods of change. In regard to risk-need-responsivity, the intersection of substance use and offending patterns may be important to understand how these criminogenic needs change over time, according to age, and the function in fostering desistance.


Aims

The aims of this research are to:

  • Plot and describe the age-crime curve among people who inject drugs
  • Determine the impact of severe mental illness on offending patterns and pathways among people who inject drugs with histories of incarceration
  • Determine the prevalence of poor psychiatric well-being among people who inject drugs with a history of incarceration
  • Characterise offending profiles and trajectories of crime among people who inject drugs with a history of incarceration

Methods

The following data sources will be used for this research project:

The Prison and Transition Health (PATH) Study

The PATH study is a prospective cohort of 400 men who inject drugs with histories of incarceration. The men were recruited from three prisons (one minimum, one medium, and one maximum security) throughout Victoria, Australia six-weeks prior to release. Following release, the men were interviewed three, 12, and 24 months post-release.

Victoria Police LEAP (Law Enforcement Assistance Program)

The Victoria Police LEAP contact database will be used to determine the age at offence for the cohort. This database is used for day-to-day operations, whereby members of the police record crime-related information. Victorian Public Mental Health Data.

The Victorian public mental health database is a statewide patient database. The database has recorded all public psychiatric inpatient admissions since 1961. Contacts with the private health sector for inpatient admissions or outpatient services are not contained within the database. For the present study, we will be primarily interested in contact with public mental health services (yes, no), and specific diagnoses for severe mental health: psychotic and mood disorders.

The primary method of analysis will be latent class analysis (LCA). LCA is a statistical model used to identify variables that are not measured directly, but measured indirectly by two or more observed variables. The observed variables are categorical, with the latent variable also being observed as categorical with different classes. LCA has been determined to be a person-centred approach to data analysis, with the emphasis on the individual as a whole. This is contrasted with the variable-centred approach to data analysis, which aims to account for the linear relationship between variables. For the present study, the latent variable of interest is the profile of offenders, with indicator variables (observed) being taken from the above listed data sources.


Significance

This research project will assist in mapping trajectories of crime and identifying periods of time of possible intervention. Moreover, this research project will assist in identifying factors fostering diversity in crime and factors fostering desistance for people who inject drugs.


Progress

Below is a brief progress report:

  • The PATH study has concluded all follow-up interviews with study participants.
  • LEAP data has been received from Victoria Police. This data is currently being cleaned.
  • Data linkage with the Victorian Public Mental Health database is in progress.

Presentations

Cossar, R., O’Keefe, D., Jacka, D., & Dietze, P. (2019) Describing client presentations at syringe dispensing machines in Melbourne, Australia: A novel method of data capture. Paper accepted for presentation at Harm Reduction International Conference, 28 April – 1 May 2019, Porto, Portugal.

Cossar, R., Stewart, A., Kirwan, A., Dietze, P., Stoove, M., & Ogloff, J.R.P. (2019). Patterns of Crime and the Age-Crime Curve in Men who Inject Drugs in Victoria. Oral presentation at the Public Health Association of Australia’s Justice Health Conference 2019, 9-10 April 2019, Sydney, Australia.

Cossar, R., Dietze, P., & Quinn, B. (2019). Dose-Response Relationship between Methamphetamine Use and Crime among People Using Methamphetamine. Oral presentation at the Public Health Association of Australia’s Justice Health Conference 2019, 9-10 April 2019, Sydney, Australia.

Stewart, A., Scott, N., Dietze, P., Cossar, R., Butler., Kirwan, A., & Stoove, M. (2019). Longitudinal changes in psychiatric well-being among male prisoners reporting injecting drug use. Oral presentation at the Public Health Association of Australia’s Justice Health Conference 2019, 9-10 April 2019, Sydney, Australia.

Cossar, R., Kirwan, A., Dietze, P. M., Ogloff, J. R. P., & Stoove, M. A. (2018). The transition from prison to community: A period of heightened overdose risk in a cohort of men with injecting drug use histories in Victoria, Australia. Paper presented at the 2018 Australasian Professional Society for Alcohol and Other Drugs Conference, 4-7 November 2018, Auckland, New Zealand. doi:10.1111/dar.12862.

Cossar, R., Dietze, P. M., & Quinn, B. (2018). Dose-response relationship between self-reported frequency of methamphetamine use and criminal activities in a cohort of metropolitan and regional/rural people using methamphetamine in Victoria, Australia. Poster presented at the 2018 Australasian Professional Society for Alcohol and Other Drugs Conference, 4-7 November 2018, Auckland, New Zealand. doi:10.1111/dar.12862.

Cossar, R., O’Keefe, D., Verdejo-Garcia, A., & Dietze, P. M. (2017). Lack of Premeditation Increases Odds of Self-Reported Syringe Vending Machine Use Among a Population of Persons Who Inject Drugs in Melbourne, Australia. Poster presented at the 2017 Australasian Professional Society for Alcohol and Other Drugs Conference, 12-15 November 2017, Melbourne, Australia. doi: 10.1111/dar.12613.

Cossar, R., O’Keefe, D., Jacka, D., & Dietze, P. M. (2017). A Descriptive Analysis of Syringe Vending Machine Use in South-East Melbourne. Poster presented at the 2017 Australasian Professional Society for Alcohol and Other Drugs Conference, 12-15 November 2017, Melbourne, Australia. doi: 10.1111/dar.12613.


Publications

Stewart, A. C., Cossar, R., Dietze, P., Armstrong, G., Curtis, M., Kinner, S. A., Ogloff, J. R. P., Kirwan, A., & Stoové, M. (2018). Lifetime prevalence and correlates of self-harm and suicide attempts among male prisoners with histories of injecting drug use. Health & Justice, 6(1), 19. doi: 10.1186/s40352-018-0077-2.

Cossar, R., Stoové, M., Kinner, S.A., Dietze, P., Aitken, C., Curtis, M., Kirwan, A. & Ogloff, J.R. (2018). The associations of poor psychiatric well-being among incarcerated men with injecting drug use histories in Victoria, Australia. Health & Justice, 6(1), 1. doi: 10.1186/s40352-018-0059-4


Timeline

2017 – 2020

Contact

For more information relating to this project, please contact Reece Cossar: