2.2. Defining In-Hospital Mortality
lung cancer, death
LUNG CANCER
We defined in-hospital mortality in SEER as (1) OS time is ≤ 1 month after diagnosis and (2) OS status is death. Patients without OS time or OS status were excluded from the analysis. Of note, patients who passed after 1 month (OS time > 1 month) were considered to have no in-hospital mortality. Although the definition is not entirely correct because of the complexity of the clinical contexts, we believe that it describes appropriately in most cases. According to previous studies, the median length of stay of lung cancer patients who passed during the first hospital stay was 18.5 days [