Fig. 2From: Etiologies, diagnostic work-up and outcomes of acute respiratory distress syndrome with no common risk factor: a prospective multicenter studyCovariates balances as measured by standardized differences across groups exposed or not to ARDS risk factors. Standardized differences are shown before (closed circles) and after (open circles) propensity score matching (including the variable “Peak inspiratory pressure”). PEEP, positive end-expiratory pressure; COPD, chronic obstructive pulmonary disease; NIV, non-invasive ventilationBack to article page