Kuderer et al., Lancet, June 20, 2020,
doi:10.1016/S0140-6736(20)31187-9 (preprint 5/28) (Peer Reviewed)
Clinical impact of COVID-19 on patients with cancer (CCC19): a cohort study
Retrospective 928 cancer patients, showing HCQ OR 1.06 [0.51-2.20]. HCQ+AZ OR 2.93 [1.79-4.79]. The relative risks of different therapies suggest that the results are overly affected by confounding by indication. Authors note: HCQ+AZ might not be the cause of increased mortality, but instead these were given to patients with more severe COVID-19.
Kuderer et al., 5/28/2020, retrospective, USA, North America, peer-reviewed, 73 authors.
risk of death, 134.2% higher, RR 2.34, p < 0.001, treatment 45 of 181 (24.9%), control 121 of 928 (13.0%), odds ratio converted to relative risk, HCQ+AZ.
This study is excluded in meta analysis: substantial unadjusted confounding by indication likely.
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.