It seems that about two thirds of US doctors, and probably the same percentage in Australia, are getting cash kickbacks from Big Pharma:
https://www.naturalnews.com/2017-03-08-65-of-doctors-are-getting-cash-kickbacks-from-big-pharma.html
https://www.sciencedaily.com/releases/2017/03/170306114211.htm
“A majority of patients in the United States visited a doctor who received payments from drug companies, but most have no clue about it, according to a new Drexel University study. About 65 percent of those surveyed as a part of the study by Genevieve Pham-Kanter, PhD, an assistant professor in Drexel’s Dornsife School of Public Health, visited a doctor within the last year who had received payments or gifts from pharmaceutical or medical device companies.