[1] GP Synergy, NSW & ACT Res & Evaluat Unit, 20 McIntosh Dr, Mayfield West, NSW 2304, Australia
[2] Univ Newcastle, Sch Med & Publ Hlth, Univ Dr, Callaghan, NSW 2308, Australia
[3] Univ Queensland, Sch Med, Discipline Gen Practice, Royal Brisbane & Womens Hosp, Level 8 Hlth Sci Bldg, Brisbane, Qld 4029, Australia
[4] Eastern Victoria GP Training, 15 Cato St, Hawthorn, Vic 3122, Australia
[5] Univ Melbourne, Dept Gen Practice, 200 Berkeley St, Carlton, Vic 3053, Australia
[6] Hunter Med Res Inst, Publ Hlth Res Program, Locked Bag 1000, New Lambton, NSW 2305, Australia
[7] Univ Adelaide, Discipline Gen Practice, 183 Melbourne St, Adelaide, SA 5006, Australia