101 Medical decision‑making competence regarding puberty suppression: perceptions of transgender adolescents, their parents and clinicians 5 adolescents’ MDC to start PS is at all ‘required’, when the adolescents might not even have a choice to make. This situation is not unique for the transgender adolescent care. For example, some patients undergoing deep brain stimulation do not have other treatment options left. Nevertheless, in the current medical model in the Netherlands, these patients still need to give their fully informed consent to the treatment (Schermer, 2011). In addition, it should be mentioned that one’s feeling of not having a choice is different from having no choice; in fact, adolescents still have a choice to proceed to treatment or not, but for them one option is significantly preferable (i.e. to receive treatment). Besides, the adolescents, both continuers and discontinuers, parents, and clinicians questioned what the term ‘understanding’ means regarding information about the treatment and its possible consequences in the context of adolescents’ MDC to start PS; to what extent should an adolescent be able to understand the information regarding PS to be decision-making competent? Furthermore, most clinicians experienced challenges while assessing MDC and mentioned that they apply their own definition of MDC depending on the characteristics of the adolescent at hand. In addition, the results show MDC is generally assessed implicitly and not in a structured way in daily practice. This is in line with what earlier research in other contexts shows (Hein et al., 2015b). Except for one Dutch quantitative study, which shows that the vast majority (89%) of the examined transgender adolescents (aged 10-18 years) about to start PS treatment are competent to consent to this treatment, there is little evidence on transgender adolescents’ MDC to start PS (Vrouenraets, de Vries, de Vries, van der Miesen, & Hein, 2021). Because clinicians indicate that they find it difficult to determine MDC, it would be desirable to develop a more uniform way to assess MDC and provide ethics support for the ethical dilemmas that are encountered when assessing MDC (Hartman, Metselaar, Molewijk, Edelbroek, & Widdershoven, 2018; Hartman et al., 2019; Hein & Hondius, 2017). Dissemination of knowledge about MDC to start PS would help to adequately support adolescents, parents, and clinicians in the decision-making process. Despite the fact that current transgender clinical guidelines state that adolescent’s MDC is a prerequisite to start PS, the guidelines hardly clarify what ‘adolescents having MDC’ means in practice. Dutch researchers have, largely based on the information gained in the current study, developed an ethics support tool (in Dutch: ‘wilsbekwaamheidswijzer’) that provides clinicians information and direction on how to deal with adolescents’ MDC. The tool provides clinical guidance on assessing adolescents’ MDC, for example regarding what aspects the adolescents should understand about the treatment before they are considered competent (de Snoo-Trimp, de Vries, Molewijk, & Hein, 2022a; Molewijk, Abma, Stolper, & Widdershoven, 2008a). Making such an ethics support tool available to clinicians in other countries as well could be very helpful. Additionally, clinicians working in transgender treatment teams in the Netherlands rated moral case deliberation, a relatively well-established form of clinical