['To identify factors associated with specific categories of charges during acute inpatient rehabilitation treatment after traumatic brain injury (TBI).', 'Prospective observational study.', 'A single Traumatic Brain Injury Model Systems (TBIMS) center.', 'Eighty-four consecutive TBIMS patients. One exploratory analysis also included all 350 patients with TBI admitted during 1999.', 'Not applicable.', 'Average daily charges for specific categories of resource use (eg, room and board, rehabilitation therapies, functional labs).', 'Room and board and rehabilitation therapy accounted for almost 90% of average daily charges. There was no linear component of change in average daily charges, but certain categories of charges were significantly higher during the first week than thereafter. Functional status at rehabilitation admission correlated with charges for respiratory, medical, and surgical supplies and with pharmacy and radiology, but not the other categories. Specific medical variables also correlated with specific charge categories. Focused chart reviews of patients with low and high charges in specific categories led to the formulation of additional predictive hypotheses.'] Does characterization and correlate of medical and rehabilitation charges for traumatic brain injury during acute rehabilitation hospitalization?