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Identifying patients' medical conditions at hospital admission provides a more accurate picture of hospital performance

Many of the publicly available hospital quality report cards are based on administrative data. However, the diagnostic codes in administrative data are not date stamped to distinguish between conditions present at the time of hospital admission (CPAA) and complications that occur after hospital admission. Treating complications as pre-existing conditions gives poor-performing hospitals "credit" for their complications. This may cause some hospitals that are delivering low-quality care to be misclassified as average- or high-performing hospitals in hospital quality report cards, concludes a new study.

Laurent G. Glance, M.D., of the University of Rochester School of Medicine, and colleagues used data from the 1998-2000 California State Inpatient Database to analyze the impact of including CPAA modifiers (included in the database) in administrative data as a date stamp indicator. They examined the performance of 394 hospitals treating patients with 1 of 7 diagnoses: coronary artery bypass graft surgery (CABG), coronary angioplasty (PTCA), carotid endarterectomy (CEA), abdominal aortic aneurysm (AAA) repair, total hip replacement (THR), acute myocardial infarction (AMI, heart attack), and stroke. They compared the model using the CPAA information (date stamp model) with another model that ignored the information present in the CPAA modifier (no date stamp model).

Forty percent of the CABG hospitals, 33 percent of the PTCA hospitals, 40 percent of the THR hospitals, and 33 percent of the AMI hospitals identified as low-performance hospitals by the date stamp models were not classified as low-performance hospitals by the no date stamp models. However, 50 percent of the CABG hospitals, 33 percent of the PTCA hospitals, 50 percent of the CEA hospitals, and 36 percent of the AMI hospitals identified as low-performance hospitals by the no date stamp models were not identified as such by the date stamp models. The inclusion of the CPAA modifier had a minor impact on hospital quality assessment for AAA repair, stroke, and CEA. The study was supported by the Agency for Healthcare Research and Quality (HS13617).

More details are in "Accuracy of hospital report cards based on administrative data," by Dr. Glance, Andrew W. Dick, Ph.D., Turner M. Osler, M.D., and Dana B. Mukamel, Ph.D., in the August 2006 HSR: Health Services Research 41(4), pp. 1413-1437.

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