PROJECT SUMMARY/ABSTRACT The purpose of this proposed study is to establish a national cohort of prepubertal transgender/gender- nonconforming (TGNC) children (and their parents), and longitudinally observe this cohort to expand the body of empirical knowledge pertaining to gender development and cognition in TGNC children, their mental health symptomology and functioning over time, and how family-initiated social gender transition may predict or alleviate mental health symptoms and/or diagnoses. Participants will be recruited and enrolled either at one of four Gender Centers dedicated to their care (Children's Hospital Los Angeles/University of Southern California; Lurie Children's Hospital of Chicago/Northwestern University; Boston Children's Hospital/Harvard Medical School; Benioff Children's Hospital/University of California San Francisco), and followed over a 2-year observational period, with clinical and behavioral data collected from prepubertal TGNC children and their parents at 6-month intervals. The proposed study will use state-of-the-art measures and utilize statistical advances in person-centered analytical approaches (i.e., latent class analysis and latent transition analysis) to address inconsistencies in prior studies, which have focused primarily on variable-centered approaches. The proposed study leverages the resources of the only NIH-funded network of US-based pediatric gender centers (Grant #R01HD082554), expanding on this current collaboration (studying TGNC adolescents) to include a younger and understudied cohort of prepubertal TGNC children. Together, these sites share a long-term goal and anticipate expanding investigation into a program of research that examines the experiences and needs of TGNC youth from early childhood through early adulthood. This proposal sets up an ideal framework to continue collecting longitudinal data from the cohort recruited for this initial work, as well as understand the additional complexities of this population based on the cohorts recruited in the companion study of peripubertal and pubertal TGNC adolescents (Grant #R01-HD082554).

PROJECT NARRATIVE To date, the youngest transgender/gender-nonconforming (TGNC) individuals have been overlooked despite the May 2011 Institute of Medicine (IOM) report, “The Health of Lesbian, Gay, Bisexual, and Transgender People,” explicitly calling for NIH-supported research on the health needs of TGNC individuals, including: (1) the collection of empirical data on TGNC-specific health care to address gender dysphoria, (2) rigorous research aimed at understanding the health implications of approaches to care, and (3) longitudinal cohort studies that incorporate a life-course perspective to examine specific experiences of TGNC individuals across developmental stages. The proposed study leverages the resources of the only NIH-funded network of four US-based pediatric gender centers (Grant #R01HD082554), expanding on this current collaboration (studying TGNC adolescents) to include a younger and understudied cohort of prepubertal TGNC children. Specifically, the study aims to expand the body of empirical knowledge pertaining to gender development and cognition in TGNC children, their mental health symptomology and functioning over time, and how family-initiated social gender transition may predict or alleviate mental health symptoms and/or diagnoses.