Fluidity in Reporting Gender Identity Labels in a Sample of Transgender and Gender Diverse Adolescents and Young Adults, Los Angeles, California, and New Orleans, Louisiana, 2017-2019.

Gender identity labels varied over time, suggesting that misclassification may occur if data from a single time point are used to define gender identity. Our study lays the foundation for launching studies to elucidate the associations between shifting gender identities and health outcomes.