1 Centre for Longitudinal Research - He Ara ki Mua and Growing Up in New Zealand, University of Auckland, Auckland, New Zealand. sarah.berry@auckland.ac.nz.
2 Centre for Longitudinal Research - He Ara ki Mua and Growing Up in New Zealand, University of Auckland, Auckland, New Zealand.
3 School of Biological Sciences, Centre for Brain Research University of Auckland, Auckland, New Zealand.
4 National Institute of Demographic and Economic Analysis, University of Waikato, Hamilton, New Zealand.
5 Department of Paediatrics: Child and Youth Health, University of Auckland, Auckland, New Zealand.
6 Starship Children's Hospital, Auckland District Health Board, Auckland, New Zealand.