Confidential interviews with more than 40 chief executives leading prominent organisations nationwide found most who join Male Champions of Change gender-equality advocacy groups were "bystanders" who neither actively support nor resist improving gender equity.

The most active in championing gender diversity in their workplace had first-hand experience with discrimination or exclusion through their daughters or female partners. More than 40 per cent of those surveyed said they were driven by moral values, such as shame and fairness.

One CEO said: "I have a wife and daughter, and I could see the struggle that my wife had gone through, and I could see the struggle that my daughter was going through, and so there was an emotional resonance."

Another said: "When I lived [overseas], people would often talk about Australia being a very sexist place. But I was defensive at the time. I thought, 'That's not the Australia I remember.' And when I came back, it struck me as true. Shame. Seriously, shame triggered my interest."

The report, which investigated why bosses join Champions of Change groups, said that despite recent investments in closing the gender pay gap and having more women in senior management roles, Australia continued to lag behind other countries.

"We have been trying to address this gender equity issue for a long time," said Professor Isabel Metz, of the Melbourne Business School, who prepared the report. "Where Australia is lagging, North America and Europe are advancing, with a strong, long-term commitment from CEOs at IBM, Sodexo and Deloitte, for example, to get women into leadership and drive gender equality."

Around the world women continue to earn less than men, are over-represented in part-time work and are less likely to rise as far in their chosen field as their male counterparts.

While the report said many chief executives in Champions of Change groups did not take action - possibly because of a lack of understanding of the business case for diversity or fear of disapproval from male peers - they were more likely to become active about equity change after gaining a better understanding of the issues.

Those identified as least likely to champion gender equity were described as "resistors", who, for example, might attribute the absence of women in leadership roles to external factors such as a small pool of female candidates applying for a job.

The report, Male Champions of Gender Equity Change, said none of the chief executives interviewed were resistors but that some admitted to being unaware of a gender equity problem or were initially sceptical about joining the Champions of Change group.

"If I go back to before 2002 … I was not even aware of the issue at all," one chief executive said.

Professor Metz said it was important that children were told from a young age that employment opportunities were not defined by gender.

"We are talking here about cultural change, and we all know that cultural change doesn't happen in a few months or a year," she said. "It takes one passionate leader, followed by another, that persistently has this issue in the spotlight, and it will have a snowball effect."