Colleagues refer to Gordon Guyatt as the “godfather” of evidence-based medicine, a title that reflects his significant contributions to the field. As a distinguished professor of medicine at McMaster University in Canada, Guyatt has played a crucial role in reshaping the landscape of medical research. His pioneering work on the GRADE framework, which evaluates the quality of evidence behind clinical recommendations, has become a standard for over 100 medical organizations worldwide, including the World Health Organization (WHO). This shift towards standardized research has provided a more scientific basis for medical practice, moving beyond the subjective judgment of senior clinicians.
However, until recently, Guyatt was also seen as a reluctant supporter of the movement against transgender health care. He had emerged as the most prominent figure associated with the Society for Evidence-Based Gender Medicine (SEGM), a group known for casting doubt on the safety and efficacy of gender-affirming care, often framing it as risky and backed by “low-quality” evidence according to the GRADE framework. His association with SEGM included speaking at their 2023 conference and co-authoring their reviews of transgender health care, which have been used to support controversial policies by the Department of Health and Human Services and various state-level bans on gender-affirming care.
This longstanding belief that Guyatt was skeptical of transgender health care took a dramatic turn in August when he and four colleagues at McMaster issued a letter distancing themselves from SEGM. They argued that their work had been “misrepresented and misinterpreted.” In a clear and emphatic statement, they expressed that it is “profoundly misguided” to label health care based on low-certainty evidence as harmful or ideologically driven. “Many of the interventions we offer are based on low certainty evidence, and enlightened individuals often legitimately and wisely choose such interventions,” they wrote.
Guyatt further asserted that using GRADE to justify bans on gender-affirming care violates the principles of evidence-based shared decision-making. In a candid conversation with SEGM representatives, he stated, “As far as I am concerned, you are not evidence-based.” This bold declaration has sent shockwaves through circles of trans health care “skeptics,” who have dissected his letter in attempts to understand the loss of a key ally.
Some skeptics have claimed that Guyatt was “tamed” or “bending the knee” to activist pressures, while others suggested he was “turning his back” on science. A writer from the Manhattan Institute even drafted a hypothetical statement he believed Guyatt should have made. A surgeon previously scrutinized for leaking medical records of trans youth accused Guyatt of prioritizing his own interests over professional ethics.
In a recent video call, Guyatt clarified his stance, calling it “unconscionable” to use their research to deny gender-affirming care. He explained that he had been unaware of SEGM’s involvement in McMaster’s transgender health research until student activists raised concerns. Upon reflection, he criticized SEGM for its lack of transparency regarding its position on medical interventions for transgender youth, stating that the group had “behaved very badly.”
SEGM has pushed back against this characterization, defending its reviews and claiming that it operates free from ideological bias. The organization argues that it had requested corrections to McMaster’s statement, alleging that external pressures had influenced the content. It insists that it has no control over the research process or the conclusions reached by McMaster’s team, stating that the university’s researchers may be operating outside the established boundaries of evidence-based medicine.
Guyatt was unfazed by SEGM’s response, emphasizing that they could formulate new rules for evidence-based medicine, but he and his colleagues had defined those standards, which are widely accepted in the medical community.
While opponents of gender-affirming care often argue that treatments are based on “weak” or “low-quality” evidence, Guyatt points out that this characterization is misleading. Many standard medical interventions, including cancer therapies and pediatric asthma treatments, are often supported by similar levels of evidence. For instance, a March study published in the journal of the American Academy of Pediatrics revealed that only 10.6 percent of treatment recommendations in clinical practice guidelines are based on the highest-quality evidence.
The language of “weak” and “low-quality” evidence serves a dual role: it is a technical term for medical professionals, while also conveying a message that can deter patients from seeking care. Guyatt explains that low-quality evidence indicates variability among individual responses, which should not preclude patients from receiving potentially beneficial treatments. He argues that it is a fundamental misunderstanding of evidence-based medicine to ban care based solely on the quality of supporting studies.
Guyatt has been involved in systematic reviews that found low-certainty evidence for various medical treatments, yet these findings have not led to similar calls for bans. He believes that the evidence supporting gender-affirming health care is comparable to that of other medical fields and should not be subject to heightened scrutiny.
The media’s portrayal of Guyatt’s systematic reviews has been starkly different, however. His research has been cited in various legal rulings that have led to the restriction of trans health care access in several states. Guyatt finds this usage of his work deeply troubling, stressing that the intent of his reviews was to inform and empower patients, not to limit their options.
Patient autonomy and values are central to the principle of evidence-based medicine, Guyatt asserts. “It is inappropriate to put zero value on autonomy,” he states, reinforcing that individuals seeking gender-affirming care deserve respect and consideration in their medical decisions.
The Society for Evidence-Based Gender Medicine had seemingly welcomed its association with Guyatt while it lasted. This small group of clinicians operates on the fringes of the medical community and has often faced skepticism regarding its claims of being free from political and ideological influences. Their focus on evidence that supports conversion therapy and bans on gender-affirming care has drawn significant criticism.
Guyatt’s disavowal of SEGM marks a pivotal moment in the ongoing debate surrounding transgender health care. His critiques of the organization not only challenge its credibility but also shed light on the ethical responsibilities of medical professionals to ensure that their findings are not misused for harmful policies. Amid rising activism and scrutiny, Guyatt acknowledges that he has reassessed his responsibilities as a scientist. “Putting out good science is not enough,” he concludes, emphasizing the importance of how that science is applied in the real world.
