[1] Univ Adelaide, Dept Med, Adelaide, SA 5001, Australia
[2] Flinders Univ S Australia, Ctr Injury Studies, Adelaide, SA 5001, Australia
[3] Queen Elizabeth Hosp, Clin Epidemiol & Hlth Outcomes Unit, Adelaide, SA, Australia
[4] Univ S Australia, Sch Nursing & Midwifery, Adelaide, SA 5001, Australia