Spare a Thought for Hilary Cass

Few have dared to fail so publicly.

by Gemma Stone

15 April 2024

hilary cass
Photo: The Cass Review

After four years, the Cass Review of gender identity services for children and young people was finally released last week. Almost immediately numerous people with ties to anti-trans campaigning began their victory laps: the review, which generally goes against the positions of trans groups and advocates, called for further restrictions on and delays to access to treatment for trans adults and youth.

It’s important to understand why the Conservatives felt it necessary to commission Dr Hilary Cass. Anti-trans groups claim that 5,000 children a year are being rushed through gender identity development services (GIDs) against their better judgement; that children being “sacrificed on the altar of gender ideology”; that their bodies are rotting from puberty blockers; that 1,000 families are lining up to sue GIDs for medical negligence towards their children; and that detransitioning rates are skyrocketing. But what did the review find? None of that.

Of 3,499 GIDs patients Cass audited, only 27% had been referred to endocrinology, the NHS department that prescribes puberty blockers and hormone therapy, after an average of 6.7 appointments. Of these, only 54% had received a prescription. Fewer than 10 of the 3,499 had detransitioned.

In the end, the anti-trans victory lap barely made it a few feet before being overtaken by hundreds of academics, experts and service users exposing the review as a sham.

Over 100 academics signed an open letter by the Feminist Gender Equality Network condemning the review as “dangerous and potentially harmful to trans children” due to its “unsound methodology, unacceptable bias [and] problematic and supported conclusions”. Therapists Against Conversion Therapy & Transphobia (TACTT) slammed the review as having an “eliminationist agenda, dressed up in the language of ‘reasonableness’”, urging clinicians to treat the Review’s findings with “extreme caution”. “Underpinning this report,” wrote trans rights group TransActual, “is the idea that being trans is an undesirable outcome rather than a natural facet of human diversity.”

The few positive responses to the Cass review from reputable organisations read as if written at gunpoint – or at best, as hopelessly naive.

Even those involved in the review have expressed dismay at how it was conducted. Cat Burton, chair of the Gender Identity Research & Education Society, one of the organisations consulted by the Cass review team, took to X/Twitter to say that “after three discussions it was obvious that the review had been written before we started. She [Hilary Cass] totally discounted evidence from trans people from the basis of knowledge or lived experience.”

In fact, Cass discounted all kinds of evidence. Cass collected 50 studies about puberty blockers and excluded half as “low quality” while only marking one as “high quality”. Many were rejected due to not having sufficient control groups.

Critics have noted that the “gold standard” of the double-blind randomised control trial – a benchmark Cass used in her review – is patently unethical when it comes to puberty blockers, not to mention impossible to implement as those receiving a placebo soon realise their puberty isn’t being blocked. On LinkedIn, Dr Jack López, a medical anthropologist based in Bradford, said he would have failed this report as an undergraduate submission.

Among Cass’s recommendations in her report was a “puberty blocker trial”. While such practices aren’t uncommon for new drugs with unknown safety risks, puberty blockers have been used safely since the 1980s, primarily for androgen deprivation therapy in the treatment of some cancers in adults. They are also sometimes prescribed to children for precocious puberty, when a child enters puberty far ahead of their age group. It isn’t the drug that’s on trial here – it’s trans children.

Cass also suggests that the rate at which young people move from puberty blockers to subsequent hormone treatments may, as anti-trans groups have warned, prove puberty blockers help cement a trans identity in these youth. Her data for this is the fact that in two (2) studies, nearly all trans youth prescribed blockers went on to take hormones. Of course, this finding could just as easily suggest that puberty blockers are being prescribed very precisely – a possibility Hilary Cass does not entertain for even a second.

While roundly ignoring the evidence of experts, the review mysteriously arrives at many of the same conclusions that anti-trans groups did years ago. Cass recommends that young adults aged 17-25 use an intermediary gender service instead of being referred to adult services, for example – a recommendation straight out of the mouth of anti-trans group Our Duty, which has long pushed to ban gender transition for under-25s. The influence of anti-trans groups like Sex Matters, Therapy First and the Society for Evidence-Based Gender Medicine, all of whom appear in the citations, can be felt throughout the review.

More worryingly still, many of Cass’s conclusions are based on evidence that does not corroborate, or in some cases, directly contradicts her findings. For example, her recommendation of an intermediate service is based on the idea that brains don’t reach maturity until 25 – a notion that Dean Burnett, a neuroscientist and the author of The Idiot Brain describes as “guff based on hearsay, misunderstanding of neuroscience or wilful ignorance”.

On closer inspection, the citation Cass uses for her assertions about young adult brain development is a 2016 study about how the adolescent brain is excellent at learning and adapting – and contains nothing that would justify delaying someone’s access to transition.

The Cass Review was hyped as the nail in the coffin for a lawless cult of child mutilators. After all that, what we got was a 400-page GCSE sociology essay that ignored decades of research in favour of pure vibes. How embarrassing.

Gemma Stone is a transgender writer and co-founder of Trans Writes.


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