In a NRO piece titled, “Lesbian Mothers’ Children”, Mark Regnerus questions the validity and viability of producing new studies based on the National Longitudinal Lesbian Family Study:
This month yielded yet another published study — which received positive media attention — based on the National Longitudinal Lesbian Family Study. The NLLFS is about to enter its third decade of following the same 78 respondents, who were “planned” and born to lesbian mothers employing artificial reproductive technology; in nearly all the families studied, the children were being raised by their biological mother and her partner. While any sociologist worth his or her degree can appreciate the laborious task of keeping track of and reinterviewing the same group of people over many years, this particular data-collection effort probably ought to be retired.
No, my misgivings are due to the great likelihood that the data sources — the respondents themselves — have been increasingly compromised, placing the very validity and reliability of the data in question. How so?
The NLLFS employs a convenience sample, recruited entirely from announcements posted “at lesbian events, in women’s bookstores, and in lesbian newspapers” in Boston, San Francisco, and Washington, D.C. As the late family sociologist Steven Nock warned, the level of sample bias such an approach introduces is significant. The lesbian parents whose children are being studied are whiter (94 percent), more educated (67 percent college graduates), of higher socioeconomic status (82 percent held professional or managerial positions), and more politically motivated than lesbians who do not frequent such “events” or bookstores, or who live in cities like San Antonio or Kansas City, or in smaller towns across the country. (Aren’t they important, too?) Anything that is correlated with educational attainment, for example — better health, more deliberative parenting, greater access to social capital and educational opportunities for children — will be biased in analyses. Any claims about a population (in this case, American lesbian parents) based on a subgroup that does not represent the whole will be distorted, since its sample is far less diverse (given what we know about it) than a representative sample would be. Indeed, there’s nothing “national” about the NLLFS.
I have no objection at all to the collection of snowball-sample data, only to its popular use as a source of information about all children of lesbian parents. If the NLLFS were simply used to understand the world of lesbian parents and their children among the elites in those three cities, then that would be just fine. But it’s not. In this case, the practical result and conventional use of its findings — and that is key — is to generalize to the population of lesbian parents across America. While researchers themselves commonly note this limitation, it is entirely lost in the translation and transmission of findings by the media to the public.
Read the entire piece on the NRO site.
Meanwhile, MercatorNet has an essay by Walter Schumm, a Professor of Family Studies at Kansas State University, that looks at how Regnerus’ controversial study is similar to and different from other studies in terms of methodology:
Use of mixed orientation households (MOMs). Much has been made of the possibility that Regnerus succeeded in gathering data from children from mixed orientation marriages (MOMs). However, many other attempts to study GLB families have involved such marriages. One study, for example, featured 72% of children who had been born into a previous heterosexual marriage before joining a lesbian couple family at an average age of over 4 years. However, the results of such studies are heralded as showing us how well lesbian families are doing, even though they involve many of the same limitations vis-À-vis MOMs as Regnerus’ NFSS study.
Funding issues. With respect to funding, many published studies have been funded by pro-gay advocacy groups and yet few report doubts about the influence of such funding on research outcomes; but since the NFSS was funded by conservative groups, such doubts are brought to the forefront.
Outcomes for children. There is considerable research – detailed in my commentary in SSR – that notes the instability of lesbian and gay parental relationships, the tendency of their children to be involved in substance abuse, and the tendency of such children to experiment with or adopt same-sex sexual behaviors or identities — results similar to those that Regnerus reported. In other words, at least some of Regnerus’s findings were very similar to results from many other studies from around the world.
Schumm expresses points of measured concern with Regnerus’ methods, but concludes that attacks on Regnerus are not based on a fair reading of his research, especially in light of related studies:
As my own review of other studies shows, however, the wholesale ad hominem attacks on Professor Regnerus and the complete dismissal of all of his methods and professionalism continue to be unjustified, even though his research – as all research – deserves careful scrutiny. His decisions about research design and analysis were within the ball park of what other credible and distinguished researchers have been doing within the past decade.