Lesbian Mothers’ Children - Is it time to retire the National Longitudinal Lesbian Family Study?

By Mark Regnerus

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. And yet it continues to appear in peer-reviewed journal articles in the health and social sciences. What exactly is the NLLFS and why do I say it should be retired?
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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.
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