The UK is Restarting a Puberty Blocker Trial Despite 25 Years of Evidence - Carrie Clark (#4)
13 March 2025
With Carrie Clark
youth-gender-medicine
The NHS is proposing a £10 million puberty blocker trial even after the Cass Review exposed systemic failures at the Tavistock. Carrie Clark of Genspect UK walks through what the Pathways study actually contains — and what it omits. The episode is a case study in how institutions, once committed to a medical pathway, resist course-correction: by redesigning studies rather than questioning premises, by excluding inconvenient voices, and by treating ideology as a research framework.
When an institution has invested heavily in a particular approach — financially, reputationally, ideologically — what does it take to change course? The NHS's proposed Pathways study, examined in detail in this episode, offers one answer: not much. Carrie Clark, Director of Genspect UK, joins Stella O'Malley and Mia Hughes to dissect a £10 million research plan that, despite arriving in the wake of the Cass Review's damning assessment of gender medicine for children, appears designed to continue rather than interrogate the same basic approach. The backdrop matters. The Cass Review found that the evidence base for puberty blockers was weak, that the Tavistock gender clinic had failed vulnerable young people, and that the NHS had not adequately followed up on the roughly 9,000 children who passed through its doors. Clark details how the NHS has not only declined to track those patients, but is now proposing a new study that replicates many of the same methodological problems. An institution has been offered the chance to learn, and appears to be declining it. Clark walks through the structure of the Pathways study and identifies what is conspicuously absent. There are no meaningful exclusion criteria for young people with serious mental health conditions or autism, a population heavily represented in gender clinic referrals. The study's framework absorbs activist language as if it were scientific terminology, and leans on self-reporting in ways that earlier research showed to be unreliable. The result is a design that looks rigorous from a distance but is shaped as much by ideology as by method. A recurring theme is the way discomfiting evidence has been minimised or withheld. The Dutch Protocol — the original basis for puberty blocker treatment in gender-dysphoric adolescents — had methodological flaws that were never adequately addressed before the model was exported worldwide. Tavistock's own Early Intervention Study never had its full results published. A major American study led by Joanna Olson-Kennedy has similarly withheld findings. Clark argues this pattern is not coincidence: when data complicates the prevailing narrative, it is managed rather than addressed. The exclusion of detransitioners from the consultation process is particularly telling. These are precisely the people whose experiences would stress-test the study's assumptions — yet their voices were not sought. This is institutional self-protection at work: not through outright dishonesty, but through the careful management of whose knowledge counts as evidence and whose is left outside the room. What the episode illuminates is a recognisable pattern in how professional institutions handle the collision between embedded ideology and mounting counter-evidence. When an institution's credibility becomes entangled with a set of claims it is no longer willing to re-examine, the mechanism is consistent: studies are reframed to produce expected conclusions, consultations are managed to exclude inconvenient witnesses, and activist frameworks are treated as neutral science. The Pathways study is not an anomaly. It is an illustration.
