47 Perceptions of sex, gender, and puberty suppression: a qualitative analysis of transgender minors 3 METHOD Participants The interviews were conducted in the context of a larger study on controversies surrounding PS in adolescents with GD. The study was approved by the institutional review board of the Leiden University Medical Centre. For the current part of the study, an empirical ethical approach was followed, using qualitative semi-structured interviews. Gender dysphoric adolescents were interviewed face-to-face in order to identify their considerations and opinions on the use of PS.Theinformantswere13adolescentswhowererecruited from the Gender identity clinic in Leiden, the Netherlands. Fourteen consecutive adolescents, and their parents/guardians if the adolescent was younger than 18 years, were asked to participate when they attended their regular follow-up appointment. Thirteen adolescents and their families agreed to participate but one mother refused participation of her child. The adolescents who participated in the study were not selected in order to be representative, in characteristics (age, sex, socioeconomic status and psychopathology), of the population seen at the Curium-LUMC clinic. They were between 13 and 18 years of age, with an average age of 16 years and 11months, and a median age of 17 years and 4 months. All adolescents, except for one, were treated with PS. The mean age at which the adolescents started treatment with PS was 15 years and 10 months. The adolescent who was not treated with PS immediately started treatment with GAH because she was above the age of 18 when treatment was indicated, which is in line with the Dutch protocol. Five adolescents were transgirls (natal boys with a female gender identity) and eight were transboys (natal girls with a male gender identity). The full-scale intelligence quotient (IQ) of the interviewed adolescents ranged between 70 and 132,with an average full-scale IQ of 99 and a median of 102. Procedure and Measures The interviewer was not involved in the diagnostics of and treatment for these adolescents. The interviewer was a child and adolescent psychologist with a Master of Science degree and interview experience. Initial interview topics were formulated after examination of the relevant literature (see supplemental data). In accordance with qualitative research techniques, the interview topics evolved as the interviews progressed through an iterative process to ensure that the questions captured all relevant emerging themes (Britten, 1995; Guest et al., 2006). The interviews contained general topics and no close-ended questions. All interviews were audiotaped and transcribed verbatim. Before each interview informed consent for participation and tape recording was obtained from the interviewed adolescents as well as their parents in case the adolescents were younger than 18 years of age. The interviews with the adolescents took between 30 and 45 minutes. Data analysis was based on the constant comparative method (Malterud, 2001; Corbin & Strauss, 2014; Vrouenraets et al., 2015). We used an iterative process wherein we continually went back to the field and interviewed new participants to collect more data. The following