1816-8949 1816-8949 S1816-89492022000100013 10.18004/anales/2022.055.01.13 Paraguay Paraguay 00 04 2022 00 04 2022 55 1 13 16 1 2017 32 234-41 2 2020 93 60-7 3 2022 4 2019 380 1843-52 5 2020 97 350-69 6 2019 9 1 1 9-18