Children of same-sex parents are doing as well or better than the rest of the population on a number of key health indicators.

That is the initial finding from the world's largest study on the children of same-sex parents, under way at Melbourne University.

The Australian Study of Child Health in Same-Sex Families collected data on 500 children nationwide, up to the age of 17.

Of the 315 gay, lesbian and bisexual parents who completed the globally recognised Child Health Questionnaire, 80 per cent were women.