Sampling bias in Brazilian studies on transgender and gender diverse populations: the two-step measure for assessing gender identity in surveys

• Published in: Cadernos de saúde pública 2022, Vol.38 (1), p.e00180420
• Main Authors: Costa, Angelo Brandelli, Rosa, Letícia de Oliveira, Fontanari, Anna Martha Vaitses
• Format: Article
• Language: English
• Subjects: Brazil; Female; Gender Identify; Gender Identity; Humans; Male; PUBLIC, ENVIRONMENTAL & OCCUPATIONAL HEALTH; Selection Bias; Surveys and Questionnaires; Systematic Review; Transgender Persons
• ISSN: 0102-311X; 1678-4464; 1678-4464
• DOI: 10.1590/0102-311X00180420

Correctly recognizing gender identity in population-based surveys is essential to develop effective public health strategies to improve the living conditions of transgender and gender-diverse populations, as well as to adequately collect data on cisgender individuals. This study aims to present the two-step measure as the best strategy for assessing gender identity in Brazilian surveys, thus we performed two separate analyses. Firstly, we conducted a systematic review concerning HIV-related care among Brazilian transgender and gender-diverse populations to assess the strategy used to identify participants' gender identity. Secondly, we re-analyzed data from a recent survey that included Brazilian transgender populations, comparing characteristics and health outcomes from the sample identified by single-item and by the two-step measure. Concerning the systematic review, from 6,585 references, Brazilian research teams published seven articles, and only one study used the two-step measure. Regarding this survey, the two-step measure recognized 567 cisgender and 773 transgender and gender diverse participants among the 1,340 participants who answered the questionnaire, whereas the single-item measure was able to recognize only 540 transgender and gender diverse people. Furthermore, 31 transgender women self-identified as "transgender men" on the single-item measure. Therefore, although scarcely used in Brazil, the two-step measure is a more accurate strategy to recognize gender identity.