Validity and reliability of a depression, anxiety and stress scale in Cuban dental students during the COVID-19 pandemic. SciELO Preprints, 2021. DOI: 10.1590/SciELOPreprints.3308. Disponível em: https://preprints.scielo.org/index.php/scielo/preprint/view/3308. Acesso em: 27 maio. 2026.