V. QUIROZ, D. REINERO, P. HERNÁNDEZ, J. CONTRERAS, R. VERNAL, and P. CARVAJAL, “Development of a self-report questionnaire designed for population-based surveillance of gingivitis in adolescents: assessment of content validity and reliability”, J Appl Oral Sci, vol. 25, no. 4, pp. 404–411, Aug. 2017, doi: 10.1590/1678-7757-2016-0511.