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Nau mai, haere mai, welcome.

The AFL2.0  study investigates the dramatic decline of smoking, drinking and drug use among adolescents to determine the drivers of this 'megatrend.'

Our findings will contribute to international efforts to understand why substance use has declined in adolescents. This work may also inform local efforts, including those by and for Māori and Pacific, to reduce substance-related harm.

Please contact the project team via the project principal investigator Jude Ball:

Tel +64 4 918 6576

About the AFL 2.0 study


Adolescent smoking, drinking and drug use have declined dramatically over the past 15–20 years in Aotearoa New Zealand and other OECD countries. This international trend is poorly understood despite its public health importance. The large and unprecedented decline in substance use is youth-specific and sits alongside international declines in teen pregnancy, juvenile crime and dangerous driving.

What is driving this trend is largely unknown. This leaves policy makers and researchers struggling to influence further positive change or prevent future reversals in the trend. Understanding the drivers of the declining substance use among Māori teens is particularly important as gaps between Māori and non-Māori remain stark, and the findings may inform health promotion efforts.

Research approach

In this qualitative study we will investigate the possible contribution of the changing functions and meanings of substance use in adolescents' lives. We will compare archival interview data collected at the peak of adolescent substance use 20 years ago, with contemporary data collected for this study.

The interviews cover friendships, lifestyle, and perceptions about substance use and non-use. They aim to address questions such as whether other practices (social media and gaming for example) are fulfilling the social functions that substance use once did (such as projecting a “cool” or “grown up” identity, bonding with friends and meeting new people).

Findings and publications

Brief summary

Journal articles

Conference presentations


Media coverage

Our people

Jude Ball (PhD) – Principal Investigator

Jude Ball imageJude completed a PhD in 2019 exploring the drivers of long-term trends in adolescent risk behaviour, in particular smoking, cannabis use, binge drinking and sexual behaviour. Her research focuses on the impact of the changing social context on youth trends, and the inter-relationships between smoking and other risk behaviours in young people.


Michaela Pettie (PhD) – Research Fellow

Michaela Pettie imageMichaela (Ngāti Pukenga, Ngāti Maru) is a wāhine rainbow community member. She completed her PhD exploring the factors involved in autism spectrum disorders in 2020. Her research interests all relate to general wellbeing and mental health, and her work provides findings that are relevant to communities and whānau.

Loleseti Poasa – Assistant Research Fellow

Loleseti Poasa 2022 image

Loleseti is of Samoan descent and is currently studying towards a Bachelor of Health degree majoring in Health Promotion, Education and Pacific Studies. Her aims are to develop hauora resources and supports for the wellbeing of Pasefika communities and to ensure inclusion and access to healthcare services.

Andrew Waa (MPH) – Māori Advisor

Andrew Waa imageAndrew (Ngā Puhi, Ngati Hine) is a co-director of the ASPIRE2025 Tobacco Control Research Centre at the University of Otago. Andrew's work includes teaching Hauora Māori, conducting Māori Health research and conducting research with Māori communities. He is involved with tobacco research, health promotion, evaluation and interventional design and urban Māori well-being.


The project is also supported by advisors including:


The AFL 2.0 study is supported by a Royal Society / Te Apārangi Marsden Fast Start Grant.

The funding proposal (20-UOO-007) was entitled Clean Teens: Understanding declines in smoking, drinking and drug use in young people's lives.

Additional support was received from the Cancer Society of New Zealand, Wellington Division.

Ethical approval

This study has been approved by the University of Otago Human Ethics Committee (ref 21/011). If you have any concerns about the ethical conduct of the research, you may contact the Committee through the Human Ethics Committee Senior Administrator, Jo Farron de Diaz.

Tel +64 3 479 8956

Any issues you raise will be treated in confidence and investigated and you will be informed of the outcome.

Related research

This study builds on the doctoral research of the principal investigator, Dr Jude Ball. You can find out more about her work through media reports and academic publications below:

  • Kids have cut the binge drinking – and we don't really know why The Detail podcast, 10 Aug 2020, Radio New Zealand.
  • Ball, J. (2019). Sex, drugs, smokes and booze: What's driving teen trends? Describing and explaining trends in adolescent sexual behaviour, cannabis use, smoking and alcohol use in the early 21st century (PhD thesis). University of Otago, Dunedin, New Zealand.
  • Ball, J., Sim, D., Edwards, R., Fleming, T., Denny, S., Cook, H., & Clark, T. (2019). Declining adolescent cannabis use occurred across all demographic groups and was accompanied by declining use of other psychoactive drugs, New Zealand, 2001-2012. New Zealand Medical Journal, 132(1500), 12-24. Retrieved from
  • Ball, J., Edwards, R., Sim, D., Cook, H., & Denny, S. (2020). What explains the decline in adolescent binge-drinking in New Zealand? International Journal of Drug Policy, 84, 102826. doi: 10.1016/j.drugpo.2020.102826
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