Wednesday, June 26, 2013

More On Distorting Study Results

The resident ex-Transsexual-for-publicity Walt Heyer is at it again.  This time, he's busy citing a bunch of studies that he claims are "proof" that cross-gender identified children do not become transsexuals.

The studies he cites are as follows:

Dr. Bernard Zuger found that feminine acting young boys do NOT become transsexual.
http://www.ncbi.nlm.nih.gov/pubmed/3180761
(no more proof needed than this)

http://www.ncbi.nlm.nih.gov/pubmed/6693867

Dr. Fred Whitam finds the same thing Zuger found
http://www.ncbi.nlm.nih.gov/pubmed/849142
http://www.ncbi.nlm.nih.gov/pubmed/7396690

Dr Colette Chiland finds the same thing as Zuker and Whitan found
http://www.ncbi.nlm.nih.gov/pubmed/3051066
The first thing I want to point out is a design issue with all of these studies.  Both Zuger and Whitam are exploring the question of whether certain childhood behaviours are predictive of adult homosexuality, and do not appear to even ask the question of transsexuality as an outcome at all.  It is also important to recognize that sexual identity is not correlated with gender identity directly.  Any study which fails to recognize this distinction is almost guaranteed to very limited in its usefulness in understanding the frequency of transsexualism in the population.

Second, as is often the case with studies involving sexual minorities, the sample size is small to begin with,  and given the extreme rarity of transsexualism to begin with, it only makes sense that small-n sample sizes have a relatively low probability of containing representative transsexuals.  Further, the odds are that the data involving a transsexual would have been discarded altogether, or possibly rolled into the male homosexual grouping during data consolidation.

Further, these are fairly old studies - dating from 1977 to 1988.  While it would have been nice if the studies had included cross-gender identity outcomes in their design, they clearly did not.  While transsexualism should have been a visible domain to researchers during that time, I doubt very much that it was widely understood as a distinct phenomenon from homosexuality, and study designs would reflect that gap of understanding.

Ironically, a few minutes exploring the PubMed database turns up the following:

Korte et. al.: Gender identity disorders in childhood and adolescence: currently debated concepts and treatment strategies
http://www.ncbi.nlm.nih.gov/pubmed/19578420
Full Text:  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2697020/

This is a 2008 publication (so already 5 years old), but it points out that there is precious little research material out there which covers the probability of childhood cross-gender identity becoming adult transsexualism.  Fundamentally, the study itself basically states that we do not know the aetiology of transsexualism, much less do we have adequate studies to fully understand whether a child who expresses cross-gender identity is in fact transsexual as an adult.  Appropriately, it does sound a note of concern around the application of puberty suppressing drugs.

Given that on this blog, the earliest references to Spack's work date back to 2007, and a quick scan of PubMed for articles bearing Dr. Norman Spack's name turns up comparatively recent articles, it isn't terribly surprising that there is a note of caution around the administration of puberty-suppressing drugs.

However, in the 2012 published WPATH Standards of Care v7 document we find the following:

An important difference between gender dysphoric children and adolescents is in the proportion for whom dysphoria persists into adulthood. Gender dysphoria during childhood does not inevitably continue into adulthood.5 Rather, in follow-up studies of prepubertal children (mainly boys) who were referred to clinics for assessment of gender dysphoria, the dysphoria persisted into adulthood for only 6-23% of children (Cohen-Kettenis, 2001; Zucker & Bradley, 1995). Boys in these studies were more likely to identify as gay in adulthood than as transgender (Green, 1987; Money & Russo, 1979; Zucker & Bradley, 1995; Zuger, 1984). Newer studies, also including girls, showed a 12- 27% persistence rate of gender dysphoria into adulthood (Drummond, Bradley, Peterson-Badali, & Zucker, 2008; Wallien & Cohen-Kettenis, 2008).
In contrast, the persistence of gender dysphoria into adulthood appears to be much higher for adolescents. No formal prospective studies exist. However, in a follow-up study of 70 adolescents who were diagnosed with gender dysphoria and given puberty suppressing hormones, all continued with the actual sex reassignment, beginning with feminizing/masculinizing hormone therapy (de Vries, Steensma, Doreleijers, & Cohen-Kettenis, 2010).
Another difference between gender dysphoric children and adolescents is in the sex ratios for each age group. In clinically referred, gender dysphoric children under age 12, the male/female ratio ranges from 6:1 to 3:1 (Zucker, 2004). In clinically referred, gender dysphoric adolescents older than age 12, the male/female ratio is close to 1:1 (Cohen-Kettenis & Pfäfflin, 2003).  [WPATH SOC V7 p. 11]
WPATH is quite frank in raising the issue of adequate long term follow-up studies of transsexuals in general, and those diagnosed in youth in particular.  I do not expect that this will change anytime soon.  More likely, it will be decades before there is an adequate body of research to be conclusive about such matters.

In the meantime, I think we can assess Heyer's most recent slam of Dr. Spack as being one more ill-informed attempt to project his own sad outcomes on all who are transsexual.


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