Data Collection

The research committees of both clinics endorsed the research project and validated the protocol for extracting information from the medical records. The collection of sociodemographic and clinical data in each clinic was carried out by a doctor of the Infectious Diseases group working as a liaison, using an anonymized file (the name and ID number of each patient was replaced by a numerical code) to guarantee the protection of the identity of each patient. Sociodemographic information, symptomatology, comorbidities, complications, hospital and ICU stay, mechanical ventilation, laboratory test, bacterial co-infections, treatment, and patient’s discharge condition were extracted. The treatment of COVID-19 in our city greatly varied throughout the months of the study, according to the findings of different published protocols, which demonstrated the uselessness of lopinavir/ritonavir, azithromycin, hydroxychloroquine, and ivermectin, leaving only the use of dexamethasone given that in our country remdesivir or tocilizumab is not available.

Selection and information biases were controlled through the medical team’s application of the case definition criteria and diagnostic tests with high validity (risk of false results tends to zero) following the manufacturer’s criteria in reference laboratories endorsed by the National Institute of Health—Ministry of Health, and also by standardizing the data extraction work from the clinical history and logical verification (inconsistent data or data outside the measurement range of each variable was not reported).