The numbers of recorded cases of child maltreatment in Australia have risen sharply in recent years, accompanied by a substantial increase in the number of children placed in out-of-home care.1 The article by Green and colleagues2 in this issue of the MJA reports a linkage study of prospectively recorded contacts of children with child protection services during early childhood and subsequent mental health service visits between 6 and 13 years of age, based on administrative data for a representative population sample of 74 500 New South Wales children commencing school in 2009.3

Much of the information on the adverse outcomes of child maltreatment is derived from retrospective studies, which are limited by the potential for recall bias and their assessment of clinical rather than population samples. Population-based longitudinal studies are more rigorous, but relatively few investigations of the consequences of childhood trauma have been published. The contribution by Green and her co-authors is therefore a welcome addition to the literature.