His primary complaint is that the Australian study used what’s called a convenience or “snowball” sample to find its 500 same-sex families, such as reaching out to same-sex parenting email lists or organizations like Gay Dads Australia. Regnerus suggests that these parents will all be biased toward positive results, even insinuating — without providing evidence — that the researchers told participants in advance what they would be asked:
I realize that 500 cases is not a number to scoff at, and that such populations are a small minority to begin with. But until social scientists decide to do the difficult, expensive work of locating gay parents through random, population-based sampling strategies — and ones that do not “give away” the primary research question(s) up front — we simply cannot know whether claims like “no differences” or “healthier and happier than” this or that group are true, valid, and on target. Why? Because nonrandom samples are not a representative reflection of the population as a whole, but rather an image of those who actively pursue participating in the study (for whatever reason, which may matter). Who knows — the ACHESS sample of parents and children could be just like the average gay or lesbian household in Australia. I have my doubts, but it’s an unanswerable question.
Regnerus’s critique doesn’t hold much weight. It very much would be ideal to find a sample of families that included a significant number of same-sex families from which conclusions could be drawn, but doing so is wholly improbable. His own study used a sample size of over 20,000 participants — each of whom received $5 for their participation — and only two of those 20,000 had actually been raised by same-sex couples for their entire childhood. Thus, Regnerus had to conflate the results of all participants whose parents ever had a same-sex relationship — mostly unstable families — to draw his fraudulent conclusions about same-sex parenting.
Regnerus and other right-wing activists have been fond of claiming that the study is “population-based” or a “national probability study.” As a scientist, I don’t even know what “population-based” means, and the data used in this study are by no means a probability sample. Regnerus’ data are from a large number of people recruited through convenience by a marketing firm — they are not a random, representative sample of the American population. Science requires random samples of the population, and that is not how this marketing firm collected their data.
While a snowball study may not be ideal, that doesn’t detract from the veracity of the Australian study’s results. In fact, it estimated there are just over 6,000 children being raised by two same-sex parents in Australia (as best they can be identified), so to capture 500 of those families is a significant result. Unlike in Regnerus’s study, all of the participants are stable same-sex families, so no conflation of unstable families is necessary; however the children are doing is how they are doing — and they’re doing great. In the end, multiple studies continue to show that same-sex parents can effectively raise children, while there is only one study that suggests otherwise, and it really didn’t involve the children of same-sex couples at all.