Retrospective 120 COVID-19 diabetes patients, showing non-statistically significantly lower mortality with existing metformin treatment.
Chen et al., 7/31/2020, retrospective, China, Asia, peer-reviewed, 12 authors.
risk of death, 33.0% lower, RR 0.67, p = 0.46, treatment 4 of 43 (9.3%), control 15 of 77 (19.5%), adjusted per study, odds ratio converted to relative risk.
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.