The Transgender Inclusive Behavior Scale (TIBS) seeks to measure transgender-inclusive behavior, specifically actions and language use that support transgender people. The TIBS was developed in the United States. This study aimed to develop a Spanish version of the TIBS and confirm the structure of the English version to explore the psychometric properties and evaluate the construct validity in new contexts. We examined predictors of transgender-inclusive behavior by conducting a comparative analysis between participants from Spain and the United Kingdom. The study involved 1,110 university students, with 545 participants hailing from Spain (375 women, 162 men, and 8 non-binary individuals) and 565 participants from the United Kingdom (368 women, 178 men, and 19 non-binary individuals). Exploratory and confirmatory factor analysis were conducted to investigate and validate the factorial structure of the TIBS. The factor analysis results for the 15 items on the scale confirmed a three-dimensional structure in both languages. The scale score reliability was excellent with a Cronbach’s alpha (α) = .95 in the British sample and with an α = .89 in the Spanish sample. Being a woman, being lesbian, gay, bisexual, trans, queer, intersex, and/or asexual, and being non-religious were the strongest predictors of inclusive behaviors towards transgender people in both countries. The correlations found indicated that people with lower sexual risk behaviors, and lower sexist, homophobic, and transphobic attitudes also presented higher inclusive behaviors towards trans people. These findings support the development of community strategies to increase the social inclusion of transgender people. The TIBS is a useful measure to track their success.
