Cannabis Cohort Research Consortium (CCRC)

Synopsis

The Cannabis Cohorts Research Consortium (CCRC) is a collaboration which stemmed from the need to better address important questions about the relationship between cannabis, other drug use, life-course outcomes and mental health in children and young adults. The CCRC is a multi-organisational and multi-disciplinary international collaboration which brings together researchers from some of the largest and longest-running longitudinal studies in Australia and New Zealand. The CCRC aims to achieve its goals by involving partners in capacity building activities, and by providing capacity to allow collaborative work to proceed to high-level grant application stage. Recent work has focused on harmonising and pooling data across individual cohorts. This approach provides a number of potential advantages including efficiency in the use of existing data; the capacity to bring together expert knowledge from across a range of disciplinary boundaries; increased opportunity for knowledge translation and dissemination; increased generalisability of findings; and, the opportunity to answer questions which cannot be answered in individual cohorts.

Summary

Study name	Cannabis Cohort Research Consortium
Study abbreviation	CCRC
Current principal investigator/s	Prof Richard Mattick, A/Prof John Horwood, Prof David Fergusson, Prof Jake Najman, Prof George Patton, Prof John Toumbourou, Prof Craig Olsson, Dr Delyse Hutchinson, Dr Edmund Silins, Prof Louisa Degenhardt
Current project managers	Prof Richard Mattick, Dr Delyse Hutchinson, Dr Edmund Silins
Cohort representative (study contact)	Prof Richard Mattick
Postal address	National Drug and Alcohol Research Centre, University of New South Wales, Sydney Sydney, NSW 2052
Phone	+612 9385 0333
Email	r.mattick@unsw.edu.au
Primary Institution	University of New South Wales (UNSW)
Collaborating Institution/s	Centre for Adolescent Health, Royal Children͛s Hospital, Parkville, Melbourne Centre for Mental Health Research, Australian National University, Canberra Centre for Social and Early Emotional Development, Deakin University, Melbourne Christchurch School of Medicine and Health Sciences, University of Otago, Christchurch, New Zealand Murdoch Childrens Research Institute, Royal Children͛s Hospital, Melbourne National Drug Research Institute, Curtin University, Perth Queensland Alcohol and Drug Research and Education, University Of Queensland, Brisbane School of Paediatrics, Royal Children’s Hospital, Melbourne School of Population Health, University of Queensland, Brisbane School of Psychology, Deakin University, Melbourne School of Sociology, Social Policy and Social Work, Queens University, Belfast Telethon Institute for Child Health Research, Perth University of Queensland, Brisbane University of Melbourne, Melbourne University of Tasmania, Tasmania
Major funding sources	NHMRC
Study website	ndarc.med.unsw.edu.au
Key reference	Hutchinson, D. M., Silins, E., Mattick, R. P., Patton, G. C., Fergusson, D. M., Hayatbakhsh, R., Toumbourou, J.W., Olsson, C.O., Najman, J.M., Spry, E., Tait, R. J., Degenhardt, L., Swift, W., Butrterworth, P., L. John Horwood (2015). How can data harmonisation benefit mental health research? An example of The Cannabis Cohorts Research Consortium. Australian & New Zealand Journal of Psychiatry, 49(4), 317-323. doi: 10.1177/0004867415571169
Are data available outside study team?	Yes. Case by case basis.
Study focus	The collaborative work between researchers uses existing data to better understand the link between cannabis, other drug use, life-course outcomes and mental health in children and young adults.
Sampling frame	A range of cohorts are involved in the CCRC including: the Australian Temperament Project (ATP), the Christchurch Health and Development Study (CHDS), the Mater-University of Queensland Study of Pregnancy (MUSP), the Personality and Total Health (PATH) Through Life Project, the Western Australian Pregnancy Cohort (Raine) Study, and 2000 Stories – Victorian Adolescent Health Cohort Study (VAHCS). To date, analyses have been conducted with: The ATP which is a longitudinal study of social and emotional development that commenced in 1983 as a sample of 2443 infants (aged 4-8 months) and their parents. The ATP has been assessed on a total of 15 occasions in childhood through to young adulthood (age 28 years); The CHDS which is a longitudinal study of a birth cohort of 1265 children born in the Christchurch, New Zealand, urban region in 1977. The cohort has now been assessed on a total of 23 occasions from birth to age 35 years; The MUSP which is a 1981 birth cohort now focused on health, developmental, behavioural and social outcomes for young adults. Assessments were conducted when the children were 6 months, 5 years, 14 years, 21 years and 28 years old; The PATH study which is a 20 year longitudinal cohort study of 7,485 young (aged 20–24 at baseline), midlife (aged 40–44 at baseline) and older (aged 60–64 at baseline) adults randomly sampled from the electoral roll of the Australian Capital Territory and the nearby city of Queanbeyan; and, The VAHCS which is a 1992 longitudinal study of a representative sample of 1943 mid-secondary school adolescents in Victoria, Australia. Participants were assessed at least once during the recruitment phase in Year 9 or Year 10, and on four other occasions during adolescence with a further three follow-ups in young adulthood to approximately age 30 years.
Year commenced	Varied between individual studies
Commencement sample	Data integrated from these cohort studies involves over 7,000 young people. To date, across various cohorts (up to n=4), we have harmonised a wide range of substance use, psychosocial and other measures (n≈35) at ages which span adolescence (≈13-17 years), young adulthood (≈18-25 years), and adulthood (≈28-30 years).
Intergenerational?	Varied between individual studies
Imaging	Varied between individual studies
Linkage	Varied between individual studies
Biosamples?	Varied between individual studies

Waves

Wave	Year	Age (mean, range)	Eligible sample
1	Varied between individual studies