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. 2021 Mar 15;9:629872. doi: 10.3389/fpubh.2021.629872

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Copyright © 2021 Monroy-Fraustro, Maldonado-Castellanos, Aboites-Molina, Rodríguez, Sueiras, Altamirano-Bustamante, de Hoyos-Bermea and Altamirano-Bustamante.

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Keyword frequency. Analysis of database stored in Mendeley regarding the words in the title, keywords, and abstract. (A) Four hundred eighty-eight articles were retrieved in the first round, (B) 35 in the second, (C) 25 in the third, and (D) 13 in the fourth. Results showed a coincidence in the most frequent words.