[영문]Objective. To determine the impact of patient characteristics, clinical conditions, hospital unit characteristics, and health care interventions on hospital cost of patients with heart failure.Data Sources/Study Setting. Data for this study were part of a larger study that used electronic clinical data repositories from an 843-bed, academic medical center in the Midwest.Study Design. This retrospective, exploratory study used existing administrative and clinical data from 1,435 hospitalizations of 1,075 patients 60 years of age or older. A cost model was tested using generalized estimating equations (GEE) analysis.Data Collection/Extraction Methods. Electronic databases used in this study were the medical record abstract, the financial data repository, the pharmacy repository; and the Nursing Information System repository. Data repositories were merged at the patient level into a relational database and housed on an SQL server.Principal Findings. The model accounted for 88 percent of the variability in hospital costs for heart failure patients 60 years of age and older. The majority of variables that were associated with hospital cost were provider interventions. Each medical procedure increased cost by