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Adding lab data and refining secondary diagnosis information improves the ability to measure hospital quality of care

Use of new billing codes and readily available numerical laboratory data has been shown to dramatically increase the accuracy of comparisons of the quality of care provided by hospitals, according to a new study sponsored by the Agency for Healthcare Research and Quality (AHRQ, contract 233-02-0088). AHRQ researcher, Anne Elixhauser, Ph.D., and colleagues found that adding the new information to current claims data improved by 24 percent the accuracy of a common measure of hospital quality: risk-adjusted inpatient mortality. The researchers used data for patients admitted to 188 Pennsylvania hospitals between July 2000 and June 2003 for heart attack, congestive heart failure, stroke, gastrointestinal hemorrhage, pneumonia, abdominal aortic aneurysm repair, coronary artery bypass surgery, and craniotomy.

Accurate measurement of clinical performance is critical to ensure the integrity of public reporting, pay-for-performance programs, and the effectiveness of quality improvement initiatives. Clinical quality in hospitals is currently measured using administrative claims data such as a patient's age, sex, principal diagnosis, secondary diagnoses, and procedures performed during hospitalization. Health care researchers have been concerned that these data are insufficient to measure hospital quality. By supplementing claims data with numerical results of 20 common laboratory tests performed on admission and limiting secondary diagnoses to those that were present at admission, the study's authors achieved levels of accuracy only 5 percent lower than were achieved using complete, often difficult to obtain clinical data. Methods used in this research study can be readily applied locally, regionally, and nationally.

In 2007, standards for claims data will enable users to distinguish between secondary diagnoses present at admission and secondary diagnoses acquired during hospitalization (complications of care). Most hospitals can already retrieve numerical laboratory data electronically.

For more details, see "Enhancement of Claims Data to Improve Risk-Adjustment of Hospital Mortality," by Michael Pine, M.D., M.B.A., Harmon S. Jordan, Sc.D., Dr. Elixhauser, and others, in the January 3, 2007, Journal of the American Medical Association, 291(1), pp. 71-76. Reprints (AHRQ Publication No. 07-R028) are available from the AHRQ Publications Clearinghouse.

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