The CATS study is a unique longitudinal study of children in metropolitan Melbourne as they approach and transition through adolescence. The study began in 2012 and follows over 1200 children from grade 3 (8-9 years of age) through adolescence. The children are assessed once every year. The study also collected information from teachers through primary school, and parents through to Wave 6 (year 8; 13-14 years). The main focus of the study is on the health and emotional development of children during the middle years of school with the aim of improving our understanding of the many influences that effect the health and emotional adjustment of children as they approach their teens. The study looks at the experiences of children and their families, their changing social context as they move into secondary school and their reactions to the biological changes of puberty. The information collected as part of this large study will help us identify when and how to promote the best health and emotional adjustment in pre-teens.

Year 2012 2013 2014 2015 2016 2017 2018 2019 2020
*During COVID-19
Wave W1 W2 W3 W4 W5 W6 W7 W8 W9 W10
Age 8-9 years 9-10 years 10-11 years 11-12 years 12-13 years 13-14 years 14-15  years 15-16 years 16-17 years 17-18 years
# 1239 1190 1204 1098 1140 1023 1066 856 881 TBC
Behavioural problems Behavioural problems
General health
Imaging Imaging
Media engagement
Mental health
Physical activity and lifestyle
Reproductive health and pregnancy
Resilience and wellbeing
Respiratory health
Sexual health and activity
Substance use
Biosamples Biosamples Biosamples
Study Summary
Study name Childhood to Adolescence Transition Study
Study abbreviation CATS
Current principal investigator/s Professor George Patton
Dr Lisa Mundy
Current project manager Dr Lisa Mundy
Primary Institution Murdoch Children’s Research Institute
Collaborating Institution/s University of Melbourne
University of South Australia
University of NSW
UCL Institute of Child Health, UK
La Trobe University, Australia
Deakin University
University of Washington, Seattle USA
University of Oregon, USA
Major funding sources National Health and Medical Research Council
Study website
Key reference for study (published study protocol) Mundy, L.K., Simmons, J.G., Allen, N.B., Viner, R.M., Bayer, J.K., Olds, T., Williams, J., Olsson, C., Romaniuk, H., Mensah, F., Sawyer, S.M., Degenhardt, L., Alati, R., Wake, M., Jacka, F. and Patton, G.C.. Study protocol: the Childhood to Adolescence Transition Study (CATS). BMC Pediatr. 2013 Oct 8;13:160. doi: 10.1186/1471-2431-13-160
Are data available to others outside study team? Yes, through study publication protocol coordinated by project manager.
Study focus (e.g. social development) The effect of puberty on health and emotional development.
Sampling frame All Grade 3 students (8-9 years of age) from a stratified cluster sample of schools in Melbourne, Australia were invited to take part.
Study type (e.g. randomised control trial, cohort, case-control) Longitudinal cohort
Year commenced 2012
Ongoing recruitment? No
Commencement sample (N) 1239
Intergenerational (e.g. offspring)? No
Imaging (e.g. fMRI, ultrasound, retinal photograph)? MRI, fMRI on iCATS nested study (n=128)
Linkage (e.g. BioGrid, VPDC, NAPLAN, Medicare)? NAPLAN (Victorian Curriculum and Assessment Authority)
Biosamples (e.g. buccal, blood, hair)? Saliva
Ethics approvals or requirements (e.g. specific, extended, unspecified, other)? This project only (Specific consent)
Future research related to this project (Extended consent)
Year Age (mean, range) Eligible sample (not deceased, not withdrawn)
2012 8.5 (8 – 11) years 1239 CATS
128 iCATS
2013 9.9 (8.8 – 11.5) years 1158 CATS
2014 10.9 (9.8 – 12.7) years 1119 CATS
2015 11.9 (10.7 – 13.5) years 1066 CATS
2016 13.0 (11.6 – 14.6) years 1175 CATS
110 iCATS
2017 13 – 14 years 1177 CATS
2018 14 – 15 years 1137 CATS
2019 15 – 16 years 1102 CATS
2020 16 – 17 years 1084 CATS
2021 17 – 18 years Ongoing

Study Contact


Project Manager

Dr Lisa Mundy

Ph: +61 3 9345 6732