1. Facultad de Postgrados, Universidad Espíritu Santo, Samborondón 092301, Ecuador
2. Ecuadorian Observatory of Occupational Safety and Health, Samborondón 092301, Ecuador
3. Department of Occupational Safety and Health, Occupational Medicine-PraxMED, Quito 170135, Ecuador
4. Universidad de Aconcagua, San Felipe 2170000, Chile
5. International Pneumoconiosis Observatory, Santiago de Chile 7500494, Chile
6. Universidad Internacional SEK, Quito 170134, Ecuador
7. Ecuadorian Society of Occupational Medicine, Quito 170519, Ecuador