COVID-19(41) Patient(19) coronavirus disease(16) required(14) age(12) Coronavirus disease 2019(11) SARS-CoV-2(11) Retrospective study(11) management(11) pandemic(11) patients(10) outcome(10) Result(10) Symptom(9) Hospitalization(9) Infection(8) manifestation(8) Pneumonia(8) intensive care(8) ICU(8) Spread(7) Health(7) Admission(7) Effect(7) retrospective(7) coronavirus(7) Oxygen therapy(7) Dyspnea(6) significantly higher(6) analyzed(6)