290 patient observational trial in the USA, not showing a significant difference with HCQ treatment overall, but showing significantly lower mortality in a subgroup of patients where HCQ is expected to be beneficial based on a machine learning algorithm.
Burdick et al., 11/26/2020, prospective, USA, North America, peer-reviewed, 14 authors.
risk of death, 59.0% higher, RR 1.59, p = 0.12, treatment 142, control 148, adjusted per study, all patients.
risk of death, 71.0% lower, RR 0.29, p = 0.01, treatment 26, control 17, adjusted per study, subgroup of patients where treatment is predicted to be beneficial.
Effect extraction follows pre-specified rules
prioritizing more serious outcomes. For an individual study the most serious
outcome may have a smaller number of events and lower statistical signficance,
however this provides the strongest evidence for the most serious outcomes
when combining the results of many trials.