• The benefits of hydroxychloroquine in this cohort as compared to previous studies maybe related to its use early in the disease course with standardized, and safe dosing, inclusion criteria, comorbidities, or larger cohort

• The pathophysiology of COVID-19 of the initial viral infection phase followed by the hyperimmune response suggest potential benefit of early administration of hydroxychloroquine for its antiviral and antithrombotic properties; Later therapy in patients that have already experienced hyperimmune response or critical illness is less likely to be of benefit

Limitations:

• retrospective, non-randomized, non-blinded study design
• information on duration of symptoms prior to hospitalization was not available for analysis
• findings are limited to hospitalized patient population

Notable qualities:

• use of a cohort of consecutive patients from a multi-hospital institution
• regularly updated and standardized institutional clinical treatment guidelines
• QTc interval-based algorithm specifically designed to ensure the safe use of hydroxychloroquine
• multi-racial patient composition
• confirmation of all patients for infection with PCR
• control for various confounding factors including patient characteristics such as severity of illness by propensity matching