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International Youth Development Study

  • Background and Aims

    IYDS_logoThe International Youth Development Study (IYDS) is a long-term study that began 2002, that looks at the development of healthy and problem behaviours among young people in the state of Victoria, Australia, and the state of Washington, United States. IYDS is one of the first studies designed to examine how cross-national cultural and policy differences affect youth development.

    IYDS aims to improve the lives of young people by:

    • Understanding how families, schools, communities and peer groups influence young people's behaviour in terms of school performance, mental health and substance use.
    • Understanding how cultural and policy differences between Victoria and Washington State influence youth development and trajectories into adulthood.
    • Investigating the effects of different school substance use policies on student behaviour and examining the impact of school discipline approaches on student behaviour, wellbeing and educational outcomes.
    • Investigating which factors early in life influence long-term health and behaviour outcomes in adulthood.

    In 2018, Victoria and Washington State will undertake further locating and surveying with participants from the middle cohort (i.e. those who were in year 7 when the study commenced). This will enable comparison of the views and experiences of IYDS participants who have grown up in Washington State with those of participants who have grown up in Victoria.


    Social Development Research Group, University of Washington and Deakin University. 


    IYDS received funding from National Health and Medical Research Council (NHMRC) 2010-2014 and the Australian Research Council (ARC) from 2010-2012.  Funding to support 2018 data collection has been received from the United States National Institute on Alcohol Abuse and Alcoholism (NIAAA).

    Key papers

    Heerde, J. A., Bailey, J. A., Toumbourou, J. W., Rowland, B., & Catalano, R. F. (2020). Longitudinal associations between early-mid adolescent risk and protective factors and young adult homelessness in Australia and the United States. Prevention Science, 21(4), 557-567.

    Stokes, M.A., Hemphill, S., McGillivray, J., Evans‐Whipp, T., Satyen, L & Toumbourou, J.W. (2020). Self-reported injury in Australian young adults: Demographic and lifestyle predictors. Australian and New Zealand Journal of Public Health. 44(2), 106-110.  .

    Heerde, J.A., Bailey, J.A., Toumbourou, J.W., Rowland, B., Catalano, R.F. (2020) Prevalence of homelessness and co-occurring problems: A comparison of young adults in Victoria, Australia and Washington State, United States. Children and Youth Services Review. 109, 104692.

    Scholes -Balog, K.E., Hemphill, S.A., Heerde, J.A., Toumbourou, J.W., Patton, G.C. (2020) Childhood social environmental and behavioural predictors of early adolescent onset cannabis use. Drug and Alcohol Review. 39(4) 384-393.

    Parks, M., Solomon, R.J., Solomon, S., Rowland, B.C., Hemphill, S.A., Patton, G.C., Toumbourou, J.W. (2020) Delinquency, school context, and risk factors in India, Australia, and the United States: Implications for prevention. Journal of Research on Adolescence. 30(S1), 143-157. 

    Epstein, M., Bailey, J.A., Catalano, R.F., Furlong, M., & Toumbourou, J.W. (2019). Does adolescent alcohol harm minimization policy exposure reduce young adult alcohol problems? A longitudinal comparison of Washington State, United States, and Victoria, Australia. Journal of Adolescent Health. 66, 713-718.

    Heerde, J.A., Bailey, J.A., Toumbourou, J.W., Catalano, R.F. (2019). Longitudinal associations between the adolescent family environment and young adult substance use in Australia and the United States. Frontiers in Psychiatry. 10:821.

    Enstad, F., Evans-Whipp, T., Kjeldsen, A., Toumbourou, J.W., von Soest, T. (2019) Predicting hazardous drinking in late adolescence/young adulthood from early and excessive adolescent drinking - a longitudinal cross-national study of Norwegian and Australian adolescents, BMC Public Health, 19 (790), 1-12.

    Rowland, B., Jonkman, H., Steketee, M., Solomon, R., Solomon, S., Toumbourou, J.W. (2019) A Cross-national comparison of the development of adolescent problem behavior: a 1-year longitudinal study in India, the Netherlands, USA and Australia. Prevention Science. 

    Prendergast, L. E., Toumbourou, J. W., McMorris, B. J., & Catalano, R. F. (2019). Outcomes of early adolescent sexual behavior in Australia: Longitudinal findings in young adulthood. Journal of Adolescent Health, 64, 516-522.

    Kelly, A. B., Evans‐Whipp, T. J., Smith, R., Chan, G. C., Toumbourou, J. W., Patton, G. C., ... & Catalano, R. F. (2015). A longitudinal study of the association of adolescent polydrug use, alcohol use and high school non‐completion. Addiction110(4), 627-635.

    Toumbourou, J. W., Evans‐Whipp, T. J., Smith, R., Hemphill, S. A., Herrenkohl, T. I., & Catalano, R. F. (2014). Adolescent predictors and environmental correlates of young adult alcohol use problems. Addiction109(3), 417-424.

    McMorris, B. J., Catalano, R. F., Kim, M. J., Toumbourou, J. W., & Hemphill, S. A. (2011). Influence of family factors and supervised alcohol use on adolescent alcohol use and harms: similarities between youth in different alcohol policy contexts. Journal of studies on alcohol and drugs72(3), 418-428.

    Evans-Whipp, T. J., Plenty, S. M., Catalano, R. F., Herrenkohl, T. I., & Toumbourou, J. W. (2013). The impact of school alcohol policy on student drinking. Health education research28(4), 651-662.

    Hemphill, S. A., Toumbourou, J. W., Herrenkohl, T. I., McMorris, B. J., & Catalano, R. F. (2006). The effect of school suspensions and arrests on subsequent adolescent antisocial behavior in Australia and the United States. Journal of Adolescent Health39(5), 736-744.

    Digital media

    Further information on can be found on the IYDS website and on their Facebook page.

    IYDS can be emailed at