Study selection and eligibility criteria
Two reviewers (P.R.M.-F. and E.M.N.-J.) independently screened the
search results and identified studies that were potentially relevant
based on their title and abstract. Relevant studies were read in full
and selected according to eligibility criteria. Disagreements between
the two reviewers were resolved by consensus.
The following elements were used to define eligibility criteria: (1)
Population: individuals with laboratory-confirmed SARS-CoV-2 infection;
(2) Intervention: nitazoxanide; (3) Comparison: placebo; (4) Outcomes:
positive RT-PCR status, composite measure of disease progression (severe
COVID-19, ICU admission or invasive mechanical ventilation), death,
serum biomarkers of inflammation (C-reactive protein, IL-6, and IL-8),
and any adverse events; (5) Study type: blinded, placebo-controlled,
RCTs. Eligible studies must report at least 1 of the outcomes of
interest. Potential overlapping populations, open-label trials, and
observational studies were excluded. Trials testing drug associations
were also excluded.