For a reason that I can not figure out there are a small but still significant portion of medical studies that automatically exclude gays from participating without an apparent scientific reason. These studies usually have requirements that the subject be in a “reciprocal relationship with a person of the opposite sex.”

Sometimes the exclusion of gays is appropriate, for example if the study were looking at how HIV spreads during male-female sex. In this example the researchers would only want heterosexual subjects. But in most studies that exclude gays from the subject pool there is no legitimate reason for the exclusion.

Brian Egleston, a bio-statistician at Fox Chase, made the observation while overseeing enrollment of patients into clinical trials at the cancer center. “When I first saw this, I thought it was a fluke. The second time, I thought I’d dig deeper,” he said.

Egleston and Roland Dunbrack Jr., a biologist, and Dr. Michael J. Hall, a medical oncologist, did a spot check of a government database of thousands of studies and turned up more examples, most of them private-industry trials. They found cases where the reason for excluding gays is not clear: tests of a drug for attention-deficit disorder, a treatment for erection problems after prostate cancer surgery, and studies on sexual function related to diabetes, depression and benign enlargement of the prostate as men age.

Currently, researchers seeking federal support for their work must explain why a study excludes a group based on gender, race or ethnicity. However, no explanation is needed for exclusion based on sexual orientation.

Joel T Nowak, M.A., M.S.W.