Pneumonia is a common postoperative complication, with a mortality of up to 40%. The Post-operative Pneumonia Risk Index (PPRI) was derived from a large cohort of general surgical patients but has ...

Notably, researchers matched the groups based on propensity scores, leaving 1,136 patients with COVID-19 pneumonia and 86 patients with non-COVID-19 pneumonia “adequate[ly] balance[d]” in ...