Trans20
Trans20 is a longitudinal cohort study comprising 618 children and adolescents. The study, which commenced in 2017, is embedded in standard clinical care at the Royal Children’s Hospital Gender Service (RCHGS). Trans20 aims to evaluate clinical outcomes of trans and gender diverse children and adolescents. Data is collected from patient during their episode of care with the service (~ yearly) and also once discharged (~every 24 months). Data is collected across multiple domains, including gender identity, mental health, physical health, quality of life and family functioning. This rich dataset offers tremendous opportunities to address important questions in the field of transgender health.
| Study Summary | |
|---|---|
| Study name | Trans20 |
| Study abbreviation | Trans20 |
| Current principal investigator/s |
Ken Pang Michelle Tollit Carmen Pace Pip Buckingham Rushani Wijesuriya Ghazaleh Dashti Cate Rayner Rachel Skinner |
| Primary Institution/s |
The Royal Children’s Hospital - RCH
Murdoch Children’s Research Institute - MCRI |
| Major funding source/s |
The Royal Children’s Hospital Foundation - RCHF National Health and Medical Research Council - NHMRC Hugh Williamson Foundation |
| Key reference for study | Tollit, M. A., Pace, C. C., Telfer, M., Hoq, M., Bryson, J., Fulkoski, N., ... & Pang, K. C. (2019). What are the health outcomes of trans and gender diverse young people in Australia? Study protocol for the Trans20 longitudinal cohort study. BMJ open, 9(11), e032151. |
| Study focus |
The Trans20 study aims to prospectively document the natural history of gender diversity in trans and gender diverse children and adolescents from Victoria, Australia, and to investigate long-term outcomes (gender, mental health, physical health, schooling, family functioning, quality of life) for those receiving gender affirming interventions. |
| Sampling frame |
Participants include patients (aged 3-17 years old) who attended the Royal Children's Hospital Gender Service in Melbourne, Australia, between February 2017 and February 2020. |
| Primary study type | Longitudinal cohort |
| Year commenced |
2017 |
| Is this study ongoing? | Yes - the study is ongoing |
| Ongoing recruitment? | No |
| Sample size (N) |
618 |
| Survey data available? | Yes |
| Imaging data available? | No |
| Linkage to administrative dataset/s? | No, no consent to link to administrative dataset(s) obtained |
| Biosamples available? | No |
| Are data available to others outside study team, with appropriate safeguards and structures in line with the cohort’s ethics and governance processes? | Yes |
| Are there any costs associated with data/sample access for approved requests? | There are usually no costs associated with access |
| Broadest type of participant consent available |
Questionnaires are completed as part of routine clinical care at RCH Gender Service and are analysed under a clinical audit framework. Long-term follow-up of patients who leave the Gender Service require specific consent. |
2025
McLean A, Hoq M, Pang KC, O'Connell M. (2025). Frequency, Timing, and Management of Erythrocytosis in Adolescents Receiving Gender-Affirming Testosterone Therapy-A Retrospective Study. Transgend Health, 10(4), 401 - 406. DOI: 10.1089/trgh.2024.0233
Moussaoui D, O'Connell MA, Elder CV, Grover SR, Pang KC. (2025). Characteristics of Menstrual Suppression and Its Association With Mental Health in Transgender Adolescents: Correction. Obstet Gynecol, 146(6), 925 - 927. DOI: 10.1097/AOG.0000000000006096
Tollit MA, Maloof T, Hoq M, Haebich K, Pace CC, Rodriguez ZM, Sial M, Payne JM, Pang K. (2025). Corrigendum to "A comparison of gender diversity in transgender young people with and without autistic traits from the Trans 20 cohort study" [The Lancet Regional Health-Western Pacific Volume 47, 2024, 101084]. Lancet Reg Health West Pac, 60, 101631. DOI: 10.1016/j.lanwpc.2025.101631
2024
Kerr JA, Paine J, Thrower E, Hoq M, Mollica C, Sawyer SM, Azzopardi PS, Pang KC. (2024). Prevalence of Eating Disorder Symptoms in Transgender and Gender Diverse Adolescents Presenting for Gender-Affirming Care. J Adolesc Health, 74(4), 850 - 853. DOI: 10.1016/j.jadohealth.2023.11.396
Tollit MA, Maloof T, Hoq M, Haebich K, Pace CC, Rodriguez ZM, Sial M, Payne JM, Pang K. (2024). A comparison of gender diversity in transgender young people with and without autistic traits from the Trans 20 cohort study. Lancet Reg Health West Pac, 47, 101084. DOI: 10.1016/j.lanwpc.2024.101084
2023
Engel L, Majmudar I, Mihalopoulos C, Tollit MA, Pang KC. (2023). Assessment of Quality of Life of Transgender and Gender-Diverse Children and Adolescents in Melbourne, Australia, 2017-2020. JAMA Netw Open, 6(2), e2254292. DOI: 10.1001/jamanetworkopen.2022.54292
Hoq M, Lami F, Tollit MA, Pang KC. (2023). Gender identity questionnaire for children: An alternative scoring approach reflecting a child's affirmed gender identity. Int J Transgend Health, 24(2), 127 - 131. DOI: 10.1080/26895269.2022.2129612
Moussaoui D, O'Connell MA, Elder CV, Grover SR, Pang KC. (2023). Characteristics of Menstrual Suppression and Its Association With Mental Health in Transgender Adolescents. Obstet Gynecol, 142(5), 1096 - 1104. DOI: 10.1097/AOG.0000000000005317
2021
Dahlgren Allen S, Tollit MA, McDougall R, Eade D, Hoq M, Pang KC. (2021). A Waitlist Intervention for Transgender Young People and Psychosocial Outcomes. Pediatrics, 148(2). DOI: 10.1542/peds.2020-042762
2019
Tollit MA, Pace CC, Telfer M, Hoq M, Bryson J, Fulkoski N, Cooper C, Pang KC. (2019). What are the health outcomes of trans and gender diverse young people in Australia? Study protocol for the Trans20 longitudinal cohort study. BMJ Open, 9(11), e032151. DOI: 10.1136/bmjopen-2019-032151
0
Buckingham P, Tollit MA, Wong G, Wijesuriya R, Hoq M, Pace CC, Pang KC. (). Social transition in young trans people accessing gender-affirming care International Journal of Transgender Health, ahead-of-print(ahead-of-print), 1 - 19. DOI: 10.1080/26895269.2025.2516678
| Study Contacts | |
|---|---|
| Principal investigator/s |
Ken Pang Michelle Tollit Carmen Pace Pip Buckingham Rushani Wijesuriya Ghazaleh Dashti Cate Rayner Rachel Skinner |
| Study Contact |
Email: genderservice@rch.org.au |