This study was carefully done, peer-reviewed, and published in a prestigious journal.
It looked at very sick, hospitalized patients with COVID-19 and tried to see if hydroxychloroquine, given with or without the antibiotic azithromycin, would help save lives.
The authors selected matching controls to account for any possible confounding effects.
We conducted a retrospective analysis to compare the 28-day mortality rate in 352 patients treated with hydroxychloroquine with or without azithromycin (HCQ-group) in our hospital with a contemporary control group of 3533 patients receiving standard of care from the Belgian Collaborative Group on COVID-19 Hospital Surveillance.
Scientists found that hydroxychloroquine did save lives, indeed:
A statistically significant reduction in crude mortality rate at 28 days was observed in the HCQ-group compared to standard of care (16.8% vs 25.9%,p = 0.001).
For those not statistically inclined, p=0.001 means there is less than one-in-a-thousand possibility of this outcome being a random bit of luck. In other words, this is a finding of a very high degree of statistical certainty.
Scientists did their utmost to eliminate any possible confounding factors, such as the effect of age and so on.
After adjustment for these variables the OR for mortality was 0.635 (95%CI 0.464–0.875). Patients who did not receive HCQ had a 57% higher risk of mortality.
Read this again: those who did not receive HCQ had a 57% greater chance of dying, all other things being equal!