A robust British review found guidelines for the treatment of children with gender dysphoria ignored standards and are based on flimsy foundations, delivering a “very hard message for people to accept,” the editor of the influential BMJ said in conversation this week with the doctor who led the review.

Pediatrician Hilary Cass’ much-anticipated report found no reliable evidence on which to base gender-affirming care for youth; the rationale for blocking puberty in young children remains unclear and muddled and that the use of cross-sex hormones in the under-18s presents numerous unknowns.