Analysis: Care at Trauma CentersIs Cost Effective
By Kerri Wachter
Elsevier Global Medical News
PITTSBURGH -- Treatment at a trauma center versus a nontrauma center was associated with an increase of 70 additional life-years per 100 patients, according to a large, multistate cohort analysis of patients.
In addition, even though care at a trauma center was found to be more expensive than was care at a nontrauma hospital, the costs associated with a trauma center were well within the widely accepted benchmarks used to judge cost effectiveness, said Ellen MacKenzie, Ph.D., at the annual meeting of the American Association for the Surgery of Trauma.
The cohort of 5,043 severely injured adult trauma patients received care in 69 hospitals in 14 states. In all, 1,085 patients died. All patients who were discharged were contacted by phone at 3 and 12 months postinjury to assess their functional status using the Short Form 36 (SF-36) health questionnaire and to determine their use of health services.
Data on costs were derived from multiple sources, including medical records, claims data from the Centers for Medicare and Medicaid Services (CMS), hospital bills, and patient interviews.
The researchers estimated the cost effectiveness of trauma centers from a societal perspective, using three standard methods: cost per life saved, cost per life-year gained, and cost per quality-adjusted life-year (QALY) gained. Using data from the National Study for Cost and Outcomes in Trauma (NSCOT) database, they included patients who died or who sustained an injury with an Abbreviated Injury Score of 3 or greater.
To estimate the incremental life-years gained, the researchers assumed that a survivor benefit from trauma center care does not extend beyond 1 year postinjury. They also discounted future life-years by 3%, "which is standard in these kinds of cost-effectiveness analyses," said Dr. MacKenzie. This analysis yielded an increase of 70 additional life-years per 100 patients in trauma versus nontrauma centers.
QALYs were calculated using adjusted values on the SF-16 (an abbreviated version of the SF-36) at 3 and 12 months postinjury, together with assumptions about how function declines with age. To estimate costs, the researchers first derived estimates of 1-year treatment costs, for which there were previous data. They then projected lifetime costs, making some assumptions about life expectancy and ongoing medical expenditures for survivors.
The added cost of treatment in a trauma center versus a nontrauma center was found to be $36,319 per life-year gained ($790,931 per life saved) and $36,961 per QALY gained--well within the cost-effectiveness ratios of $50,000 to $100,000 per life-year gain deemed acceptable in the literature. The higher price tag associated with treatment at a trauma center is attributable largely to the costs incurred during the initial hospitalization at a trauma center versus a nontrauma center.
The difference between the two types of facilities in per-lifetime patient costs was estimated to be $20,000, explained Dr. MacKenzie, chair of the department of health policy and management at the Johns Hopkins University's Bloomberg School of Public Health.
One-year treatment costs derived for the initial hospitalization included all transport costs and costs associated with treatment at the emergency department of another hospital prior to transfer, subsequent inpatient care, outpatient and home health care, and informal care provided by family and friends. For patients enrolled in Medicare, the researchers used detailed claims data obtained from CMS. Costs were calculated from charges by applying cost-to-charge ratios computed on the Medicare cost reports that were specific to hospital and year of treatment. Data were obtained from several different sources for patients who were not on Medicare.
These cost-effectiveness estimates have long-term importance for the trauma specialty, said Dr. Robert C. Mackersie, the invited discussant for the paper. "It's one of the few studies estimating the value and cost effectiveness of providing trauma care ... and provides data that are likely to be critical in our efforts to persuade legislators and the public to invest in trauma systems infrastructure," said Dr. Mackersie, professor of surgery and director of trauma services at San Francisco General Hospital.