Physicians’ preference towards the non-evidence based hydroxychloroquine treatment for COVID-19: the pandemic effect

Luis Claudio Correia, João Ricardo Pinto Lopes, Flávia Barreto Garcez, Edmond Le Campion, Guilherme Barcellos, José Augusto Barreto-Filho


OBJECTIVE: To evaluate whether there is a "pandemic effect" promoting irrational medical reasoning. METHODS: Cross-sectional study. Setting state medical councils were asked to send all registered physicians two sequential email invitations to complete a Google Form questionnaire. Between April 15 and May 3, 2020, 370 doctors answered our questionnaire with questions about the prescription of hydroxychloroquine for COVID-19 and vitamin C for sepsis. The questionnaire had a five-point Likert scale (greater number, greater support) on the degree of propensity to prescribe the medication and a binary question (yes or no) to express the doctor's final decision to prescribe. These two questions, in the same order, were asked for scenarios of mild, moderate and severe cases. RESULTS: The propensity to prescribe hydroxychloroquine for COVID-19 increased with the severity of the clinical presentation: for mild cases, 37% (95% CI 32%-42%) of the physicians chose "yes", increasing to 68% (95% CI 63%-72%) and 89% (95% CI 85%-92%) for moderate or severe cases, respectively (Cochran's Q test: P<0.001). The medians and interquartile ranges of the Likert scales for hydroxychloroquine were 2 (1-4), 4 (2-4), 4 (4-5) in mild, moderate and severe cases of COVID-19 (Friedman test: P<0.001). CONCLUSIONS: The propensity of the Brazilian physician to prescribe hydroxychloroquine for COVID-19 is high and, according to the severity of the disease, ranged from 37 to 89%. On the contrary, the propensity to prescribe vitamin C for sepsis, a non-pandemic situation, was lower and not associated with clinical severity. Our data suggest a "pandemic effect" promoting irrationality in medical reasoning.


COVID-19. Evidence-Based Medicine. Hydroxychloroquine.

Full Text:




  • There are currently no refbacks.

Copyright (c) 2020 João Ricardo Pinto Lopes, Luis Claudio Correia, Flávia Barreto Garcez, Edmond Le Campion, Guilherme Barcellos, José Augusto Barreto-Filho

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.

This journal has been indexed and/or catalogued in the following database:



Journal of Evidence-Based Healthcare | ISSN 2675-021X

Updated 01/03/2020

Creative Commons License