Entry › For clinicians · Last reviewed 2026-05-16

For clinicians and researchers

A structured entry for health professionals and researchers: primary publications, evidence reviews, methodological criticism and international policy.

1. Primary literature

• Cohen-Kettenis & van Goozen 1998 — first case report.
• Delemarre & Cohen-Kettenis 2006 — formal protocol description.
• de Vries 2011 — first follow-up n=70.
• de Vries 2014 — "Amsterdam study" n=55.
• Steensma 2013 — desistance.
• Follow-up studies — overview — all later cohort publications (van der Loos, Brik).
• Original publications — chronological list with PubMed references.

2. Systematic reviews and HTAs

• Cass Review (2024) — University of York systematic reviews.
• SBU (2022, Sweden).
• COHERE (2020, Finland).
• Karolinska policy (2021).
• NICE evidence reviews (2020) — see UK dossier.
• Florida AHCA review (2022).

3. Methodological criticism

• Methodological criticism — overview.
• Sample size and attrition — limitations of the n=55 cohort.
• Replication attempts — Costa 2015, Carmichael 2021.
• Biggs puberty blocker overview.
• Levine et al. critiques.

4. Clinical policy in NL and internationally

• Guidelines Netherlands — Quality Standard Transgender Care.
• Guidelines international — Endocrine Society, WPATH SOC-8, AWMF.
• International comparison — policy per country in table form.
• Current status Netherlands.

5. Response from the original researchers

The Amsterdam UMC researchers (de Vries, Steensma, van der Loos) have responded to criticism in several peer-reviewed publications. See /debate/response-vumc-amsterdam-umc/.