Fig. 3From: Developing a mortality risk prediction model using data of 3663 hospitalized COVID-19 patients: a retrospective cohort study in an Egyptian University HospitalKaplan–Meier curves for cumulative survival of COVID-19 patients stratified by age groups (a), smoking status (b), presence of comorbidities (c), presence of symptoms (d), and the severity of patients’ condition on admission (e)Back to article page