evidence: This memo addresses the frequently made claim that "gender affirming" hormonal and surgical interventions for minors are appropriate because most major medical organizations in the U.S. support them. While it is understandable that doctors and their patients should want to follow guidelines issued by professional medical groups, it is important to recognize that these groups don’t always get the science right. [...] The three main American medical organizations to have recommended "gender affirming care" for minors are the American Academy of Pediatrics (AAP), the Endocrine Society, and the World Professional Association for Transgender Health (WPATH). Other organizations, including the American Medical Association, have issued public statements in support of the use of hormones to address gender dysphoria, but without discussing the research. [...] Because the Dutch study, published in 2011 and 2014, is widely regarded as the gold standard of research in support of "gender affirming" hormonal and surgical interventions for minors, its five main problems[9] should be well understood: