Background Coronavirus disease 2019 (COVID-19) has resulted in millions of mortality cases and significant incremental costs to the healthcare system. Examination of CRP and D-dimer were considered to have higher costs, and the use of simple hematological parameters such as lymphocyte, neutrophil, and white blood cell (WBC) which have more affordable costs would be cost-saving. Radiological imaging complements clinical evaluation and laboratory parameters for managing COVID-19 patients. Therefore, categorizing patients into severe or non-severe becomes more defined, allowing for earlier interventions and decisions of hospital admission or being referred to a tertiary hospital. Purpose To evaluate the variables correlated with poor outcomes in COVID-19 patients. Patients and Methods This was a retrospective study on COVID-19 patients in a secondary referral hospital in treating COVID-19 in Indonesia. Demographic, clinical data, laboratory parameters, CXR (analyzed using a modified scoring system), and prognosis were collected through electronic nursing and medical records. Results This study included 476 hospitalized COVID-19 patients. Severe patients were commonly found with older age (median of 57 vs 40), dyspnea (percentage of 85.2% vs 20.5%), higher CXR score (median of 7 vs 5), higher levels of neutrophil (median of 79.9 vs 68.3), and lower lymphocyte levels (median of 13.4 vs 22.7), compared to non-severe patients. These variables were known to increase the odds of severe disease. Older age (median of 57 vs 48), SpO 2 <94% room air (percentage of 87.4% vs 31.5%), higher CXR score (median of 8 vs 5), and higher respiratory rate (median of 25 vs 20) were found higher in death patients and were known to increase the odds of death outcome. Conclusion The simple blood tests (neutrophil and lymphocyte) and modified CXR scoring system are useful in risk stratification for severe disease and mortality in COVID-19 patients to decide the earlier interventions and treatment.