One can tell if medical reviews are high quality: their evidence and recommendations are accepted and acted upon (copied) widely outside the jurisdiction in which they were originally proposed.
There is a recognised, established hierarchy of assessment of the quality of medical evidence, and “being adopted by other countries” isn’t one of them. The systematic reviews that underpin Cass are of the highest quality evidence.
There are multiple examples of poor quality medical reviews being adopted geographically widely, but of course the most notable is WPATH’s SOC8. The idea that SOC8 is good because it was adopted widely is laughable. Other examples in medicine exist. Equally, countries have produced high quality medical reviews on different subjects that don’t necessarily get seen elsewhere. I don’t know where you get the idea that widespread adoption is an endorsement of quality.
That aside, there is actually strong appetite for adoption of the recommendations of Cass, because many recognise its quality and also to avoid reinventing the wheel. Many people in many jurisdictions have a strong mood for this, not a slight mood.
What there is though is a slight mood to adopt it from gender clinicians. Take for example, in Australia where the Cass Review was introduced as evidence in the case by a mother wanted to transition her child, and the judge noted, in respect to the testimony of Michelle Telfer, that the Cass review “was contrary to her entire life’s work”. The Cass Review was introduced by the mother’s team, and the gender clinicians argued the Cass Review was flawed, but the judge read it and considered it an important piece of evidence relevant to the medical transition of children.
https://www.austlii.edu.au/cgi-bin/viewdoc/au/cases/cth/FedCFamC1F/2025/211.html
So the Cass Review has been relevant in other jurisdictions already. It helped stop a child from being medically transitioned in Australia.
Finally, the final Cass Review was published in April 2024. It’s only been just over a year and that year has been spent wearily arguing against spurious and false “takedowns” of it, which are obviously nonsense. The first country to ban lobotomy was the Soviet Union in 1950. It took more than 20 years for some other countries to follow suit. 15 months is nothing.