The author of a heavily discredited study published last year which claimed that children were put at a disadvantage with gay parents, has thrown his weight behind a new, very similar study, in Canada.

The Regnerus study, published in July 2012, was titled “How Different Are The Adult Children of Parents Who Have Same-sex Relationships? Findings from the New Family Structures Study”.

He compared the lives of children raised by parents gay relationship, of any length, with those who had grown up with straight, married parents. The first group appeared to be more likely to be in therapy, have extra marital affairs and experience other negative outcomes in later life.

Regnerus authored the new article titled: “A Married Mom and Dad Really Do Matter: New Evidence from Canada”. It refers to a study published last week in the journal called, Review of the Economics of the Household, by Douglas Allen.

He takes examples from the study, such as the claim that children of gay parents are 35% less likely to graduate from high school than those with married, opposite-sex, parents.

Describing “dramatically low graduation rates” of children with same-sex parents, Regnerus says that girls do worse than boys.

While the Regnerus study was criticised as it compared children with any gay parent, single, separated or divorced, to only married opposite-sex couples, he addresses that issue, claiming that the new study, based in Canada, is more accurate.

He concludes, asking: “Might the American Psychological Association and American Sociological Association have been too confident and quick to declare “no differences” in such a new arena of study, one marked by the consistent reliance upon small or nonrandom “convenience” samples? Perhaps. Maybe a married mom and dad do matter, after all.”

The original study by Regnerus was described as “flawed and misleading”, by many, yet is still cited by some opposed to same-sex adoption.