"Everyone has a right to, like, check their box:" findings on a measure of gender identity from a cognitive testing study with adolescents.

Efforts to monitor the health of transgender youth, a small but high-risk population, are hindered by a lack of knowledge about how to accurately measure gender identity. Adolescents (n = 30) participated in semistructured qualitative interviews after completing a close-ended transgender-inclusive measure of gender. Interviews explored item comprehension and respondent burden. Participants, who were diverse in age (range = 15-21), gender identity, sexual orientation, and race-ethnicity, were accurately classified as male, female, or transgender. All youth understood transgender as a difference between the physical body and a person's internal sense of self. Nontransgender youth frequently used an example (a woman in a man's body) in their explanations and were largely supportive of the transgender options. Most transgender youth found a response option that they felt was appropriate. Transgender response options were added to a gender measure without impacting the accuracy of nontransgender responses or burdening the nontransgender adolescents in our sample. A modified measure (Gender: male; female; transgender, male-to-female; transgender, female-to-male; transgender, do not identify as exclusively male or female) is recommended for testing in samples that vary by age, race-ethnicity, socioeconomic status, language, and geography. Additional suggestions for research in this area are provided.