Australian research shows a small group of doctors are responsible for half of all patient complaints.
The research published in the British Medical Journal was carried out at Melbourne University and led by New Zealander Marie Bismark, a doctor and lawyer specialising in medical law issues.
The team studied almost 19,000 complaints by patients against 11,000 doctors over a decade, in the largest such study ever carried out in Australia.
Three percent of doctors accounted for nearly half of all complaints.
Male doctors accounted for 79% of all complaints, almost half of them GPs.
Researchers say there is a pressing need for interventions that address the behaviour of doctors who are the subject of many complaints.