Jennifer Block's piece in the BMJ, which focuses on the scientific evidence on gender-affirming hormone treatment in children and adolescents, is not a scientific study. It is a journalistic article, very well documented both in terms of the scientific literature she reviews, and the interviews she conducted with clinicians involved in the issue. Although it focuses on the United States and American medical associations, this issue affects the entire Western world.    

In recent years, the United States and the rest of the West has seen an increase in children expressing gender incongruence and gender dysphoria. Jennifer Block reviews both the pros and cons of puberty-blocking and sex hormone treatments for children and adolescents. These treatments are mentioned in guidelines from the World Professional Association for Transgender Health (WPATH), the American Academy of Pediatrics (AAP) and the Endocrine Society (ES) in the United States. Her piece also discusses decisions made by health authorities in the UK, Sweden, Finland, France, Australia and New Zealand, signalling precautions to be taken when administering these treatments, due to the lack of solid long-term clinical research. The article also presents conflicting views of clinicians about existing evidence on the efficacy of such treatments.  

Block's interviewees have played an important role in drafting or criticising treatment guidelines. However, we need to read her article in great detail to understand that WPATH, AAP and ES explicitly say that treatments are administered after a thorough psychological and psychiatric assessment of children and adolescents—never on mere demand. The piece correctly mentions the so-called 'Dutch protocol' of treatment. However, the article does not elaborate on how [the protocol] establishes which children are immediately eligible for treatment with [pubertly] blockers, and which will be eligible later if they meet psychological assessment requirements. This shortcoming might be due to the article’s focus on [gender] affirmation treatment only.     

Block's piece which, I insist, brings together different opinions, is well structured and provides a faithful picture of the current controversy about hormonal affirmation treatments in children and adolescents. This controversy is linked to other issues of social learning, cognitive development, clinical experience and the effect of hormones during development—and the article doesn’t go into these.