You may often see articles in the media claiming that "research has shown" that children of same-sex couples are thriving, in fact are physically and psychologically doing just as well as, or even better than, children of couples who are -- let me use this currently underused word -- normal.

Are these works reliable?

In July such a study, carried out in Australia, was much trumpeted by that pillar of "progressive" thinking, the Washington Post, under the headline "Children of same-sex couples are happier and healthier than peers, research shows".

Researcher Simon Crouch and his team at the University of Melbourne surveyed 315 homosexual parents with a total of 500 children across Australia.

Crouch writes:

We found that children from same-sex families scored, on average, 6% better on two key measures, general health and family cohesion…

In spite of doing well, many children did experience stigma, which was linked to lower scores on a number of scales.

In short, when children perform well it's due to same-sex parenting. When they perform not so well, it's due to stigma against same-sex parenting. A win-win situation for homosexual agitators.

But this apparent bias in the interpretation of the results is not the only, or even the main, problem with this study.

The method used in the Australian Study of Child Health in Same-Sex Families (ACHESS) is the biggest obstacle to taking its outcome seriously.

Mark Regnerus, associate professor of sociology at the University of Texas at Austin, research associate at its Population Research Center, has analysed the ACHESS's methodology both when an interim report appeared in 2012 and now, after the completion of the research.

He is concerned by the sampling approach of the interim report:

Initial recruitment will . . . include advertisements and media releases in gay and lesbian press, flyers at gay and lesbian social and support groups, and investigator attendance at gay and lesbian community events

And by this part of the study's methodology section:

Three hundred and ninety eligible parents contacted the researchers.

This is not a random sample, but a self-selected sample. Randomisation is one the most crucial parts of scientific research. The sample here is not representative of average same-sex households with children:

To compare the results from such an unusual sample with that of a population-based sample of everyone else [which is random] is just suspect science. And I may be putting that too mildly.

The ACHESS includes a disproportionate number of children born in new ways: 80% of those with female parent(s) were born through home insemination or assisted reproductive technology (ART), and 82% of those with male parent(s) were born via surrogacy.

Most families who can afford the expense of ART and surrogacy are likely to belong to the homosexual socioeconomic elite, the only kind of people this study's sample was likely to comprise. Also significant: when compared to a random sample of all other families, there were few unplanned pregnancies among the ACHESS parents.

In addition, "this non-random sample reflects those who actively pursued participating in the study, personal and political motivations included"; those who selected themselves for the study knew in advance its intentions, subject and political significance (so much for "blinding", another requirement of research methodology); and -- wait for this -- the actual children were not asked to report about themselves, only their parents reported about them, with all the obvious high risks involved in trusting parents’ self-reporting on their parental skills as shown by their children's outcome -- also known as risks of “social desirability bias,” the tendency to portray oneself as better than one actually is -- without an attempt to independently verify the facts.

Taking into account all these circumstances, Professor Regnerus declared himself surprised that the differences (3%-6%) between the ACHESS parents and the rest of the population were so small.

Which confirms once more that trusting the mainstream media on the complex and regrettably fashionable subject of homosexual marriage and its corollary, adoption, is not a good idea.

A Pew Research study showed how disconnected the media are from public opinion on this topic. In the news media, stories sympathetic to same-sex marriage in the 2-month period covered outnumbered those unsympathetic to it by a margin of more than 5-to-1: the former constituted 47% of all treatment of the subject, the latter 9%. In public opinion, by contrast, the percentage of respondents in favour of legalisation of homosexual marriage was 51%, while against was 42%.

This media bias is consistent with the their highly critical coverage of the New Family Structures Study (NFSS), a work overseen by Professor Mark Regnerus in which he examines nearly 3,000 adult children from 8 different family structures and evaluates them within 40 social and emotional categories.

The NFSS, he describes,

elected to talk to the children after they had grown up, to skip the parents entirely to ensure a more independent assessment, not to broadcast our key research questions in the title or initial screener questionnaire, and to locate participants randomly in a large population-based sample. If you’ve been paying attention, however, you’ll know that my NFSS studies -- which mapped 248 respondents who told us their mother or father had been in a same-sex relationship -- came to rather different conclusions than the ACHESS study has.

In his study, published in Social Science Research in 2012, Regnerus writes:

[T]he empirical claim that no notable differences exist must go.

The NFSS's results showed that children who remain with their intact biological families were better educated, were in better mental and physical health, reported overall higher levels of happiness, displayed less drug use and less criminal behaviour.

The greatest negative outcomes were found among children of lesbian mothers, contrary to faulty studies popularised by the media. The NFSS found negative outcomes for lesbians' adult children in 25 of 40 categories, including far higher rates of sexual assault (23% of lesbians' children were touched sexually by a parent or adult, compared to 2% raised by normal married parents), higher levels of depression, worse physical health, more marijuana use, and greater unemployment (69% of lesbians' children were on welfare, compared to 17% of those with normal married parents).

Regnerus’ research disproved an often-cited 2005 brief by the American Psychological Association (APA) that concluded: "Not a single study has found children of lesbian or gay parents to be disadvantaged in any significant respect relative to children of heterosexual parents." This sentence has now been removed from the APA's website.

And the confidence behind that assertion will be invalidated again and again, as more research unearths the problems associated with homosexual parenting and/or adoption.

One such investigation is that by associate professor at Louisiana State University Loren Marks, published in Social Science Research.

His work reviews the 59 published studies cited by the APA to support its above-quoted claim.

Marks found them wanting in various areas, including lack of homogeneous sampling, absence of comparison groups, presence of contradictory data, and paucity of long-term outcome data. The scope of the children’s outcomes studied was too limited: they focused on "gender roles" and "sexual identities", while neglecting to examine the children’s education outcomes, employment, risk of substance abuse, criminal behaviour, or suicide.

The conclusion is that strong assertions, including those made by the APA, were not empirically warranted.

This debunking is particularly significant, in view of the fact that the APA-endorsed studies have been used in attempts to influence legal decisions in European and American courts, with claims like "no objective scientific evidence exists to justify different treatment of same sex couples who wish to adopt", "all reputable scientific studies have shown that the children of lesbian and gay parents are no more likely to suffer from emotional or other problems than the children of heterosexual parents", and "a considerable body of professional literature provides evidence that children with parents who are homosexual can have the same advantages and the same expectations for health, adjustment, and development as can children whose parents are heterosexual."

There's still work to do, but we are on the right track.

Enza Ferreri is an Italian-born, London-based Philosophy graduate, author and journalist. She has been a London correspondent for several Italian magazines and newspapers, including Panorama, L’Espresso, La Repubblica. She is in the Executive Council of the UK’s party Liberty GB.

She blogs at www.enzaferreri.blogspot.co.uk.