Open letter to the President of the APA re Falsification of GID prevalence results by the APA Task Force on Gender Identity and Gender Variance [PDF]



September 5, 2008



To: Alan E. Kazdin, Ph.D., President, American Psychological Association


Cc: Alice M. Young, PhD, Chair, Board of Scientific Affairs;

Peter Ornstein, Chair, Publications and Communications Board;

Gilbert H. Newman, PhD, Chair, Board of Educational Affairs;

Margaret Schneider, Ph.D., Chair, Task Force on Gender Identity and Gender Variance;

APA Division 44 officers, committee chairs and task force chairs


Dear Dr. Kazdin:

The APA's recent "Report of the Task Force on Gender Identity and Gender Variance" was released with considerable public fanfare and claims that the "APA resolves to play (a) leading role in improving treatment for gender-variant people."


That report has already come under fire for perpetuating "gender identity disorder (GID)" as a stigmatizing label for gender-variant people, and for failing to distance the APA from psychiatric labeling of transitioners as mentally-ill. The APA is also criticized for including trans-reparatist therapist Ken Zucker on the Task Force, lending credibility to his inhumane clinical methods. As you may know, an international petition gained over 9,500 signatures protesting Zucker's role in overseeing revisions of the section on “sexual and gender identity disorders” in the DSM-V.


I am writing to alert you to yet another serious problem: 


The Task Force pronounced the prevalence of GID to be 1:11,900 (MtF) and 1:30,400 (FtM), grossly underreporting those prevalences by a factor of at least 10 to 20, as exposed in the following investigative report (also attached):


"Falsification of GID prevalence results by the APA Task Force on Gender Identity and Gender Variance"


That investigative report found as follows:

The Task Force’s numbers were taken from counts of sex reassignments at a Dutch gender clinic way back in the 1980's. The Task Force misrepresented those numbers as being counts of gender dysphoric people, making gender dysphoria seem far less prevalent than it really is. Furthermore, the Task Force failed to mention that internal errors in the Dutch report had caused its results to already be too small by a factor of four, and disregarded a recent study by Olyslager and Conway that had exposed those errors. 


The Task Force then stated their results to three significant figures, as if they were accurate to within a small +/- percentage, while failing to report known sources of estimation error that can cause the numbers to be too low. They also failed to mention recent scientific studies that reveal GID prevalence to be on the order of 1:1000 to 1:500 or more, values far higher than those the Task Force presented.


Who might be responsible for those falsifications and misrepresentations?

It appears that the Task Force relied on Ken Zucker and Anne Lawrence for the section on prevalence. Zucker and Lawrence are considered WPATH's 'experts' on prevalence, having been assigned responsibility for coordinating revisions of that section for the 7th Edition of the SOC. Furthermore, Zucker presented the exact same numbers for GID prevalence at the WPATH 2007 Symposium as those presented in the Task Force report. Olyslager and Conway had warned of the errors in Zucker's presentation during that Symposium, but their warnings went unheeded by Task Force members present at the Symposium. 

Why do the prevalence numbers matter?

Factors of 20 are important: By maintaining the old misimpression that fewer than 1 in 10,000 people experience gender dysphoria and may need to transition, the APA is perpetuating the illusion that transgenderism is an extremely rare "disorder". If more people realized that at least 1 in 500 people experience gender dysphoria, transgenderism would increasingly be seen for what it is, namely a natural variation in gendering. 


Furthermore, by declaring gender dysphoria to be incredibly rare, trans-reparatist therapists such as Zucker can assure parents it's extremely unlikely their gender-variant child will ever transition, suggesting that all the child needs is minor gender-repairs to avoid that "bad outcome".


Meanwhile, it is increasingly obvious that gender transitions are not extremely rare, and that the APA is totally out of contact with that reality on the streets.

What to do?

It matters not whether the APA Task Force's falsification of prevalence values was intentional or whether it was due to carelessness, ignorance and/or group-think about old, oft-cited numbers. What matters is that the APA must terminate its propagation of erroneous trans-prevalence values and correct the Task Force report accordingly.


Lynn Conway

Professor of Electrical Engineering and Computer Science, Emerita
3640 CSE Building
University of Michigan, Ann Arbor, Michigan 48109
Member, National Academy of Engineering  


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