Risk-adjusted clinical quality indicators: indices for measuring and monitoring rates of mortality, complications, and readmissions.

This article describes a risk-adjusted approach for profiling hospitals and physicians on clinical quality indicators using readily available administrative data. By comparing risk-adjusted rates of mortality, complications, and readmissions to peers, national norms, and benchmarks, this approach enables purchasers and providers to identify both favorable and adverse outcomes performance.

Risk-adjusted quality outcome measures: indexes for benchmarking rates of mortality, complications, and readmissions.

This article describes a risk-adjusted approach for profiling hospitals and physicians on quality outcomes using readily available administrative data. By comparing risk-adjusted rates of mortality, complications, and readmissions to rates for peers, national norms, and benchmarks, this approach enables purchasers and providers to compare the performance of providers in terms of both favorable and adverse outcomes.

Indices for monitoring hospital outcomes in developed countries.

We discuss some of the challenges facing hospitals in developed nations, with special attention to the need to monitor and evaluate hospital performance. In particular, there is a need for quality indicators that measure the effects of treatment, and are risk-adjusted, so that valid comparisons of outcomes can be made across hospitals that treat different types of patients. Until recently, only very crude quality indicators have been available for comparing the performance of different hospitals. We describe three risk-adjusted indices for comparing the outcomes of hospital care, focusing on the construction and validation of these measures. We discuss the uses of these tools for identifying problems and for monitoring outcomes of care within a hospital, including screening medical records for peer review, identifying variations in outcomes across various subgroups of physicians, and comparing changes in outcomes following various changes in the delivery system. Possible applications at the regional, national and international levels are then discussed, with special emphasis on the use of these tools for measuring the size of the gap between the efficacy of a technology, as determined through randomized controlled trials under stringent protocols, and the effectiveness of the same technology once it is exported, and then used under true practice conditions in another country.

The measurement of mortality. A risk-adjusted variable time window approach.

This paper describes the development of risk-adjusted mortality indices (RAMI) using 1985 MEDPAR data from 657 hospitals. The RAMI methodology is adopted from the Commission on Professional and Hospital Activities, however, both inhospital and post-discharge deaths are counted within time windows that vary by clinical condition. Five different RAMI measures (expected deaths/observed deaths) are developed, compared, and aggregated into various hospital characteristic strata. These measures vary by which discharge is held responsible for deaths within a time window, and whether or not inhospital deaths that occur beyond the time window are included. The RAMIs using varying time windows are compared with the RAMIs based upon inhospital deaths only. The inhospital RAMI was higher for the nonteaching hospitals (.95) as compared with the major and minor teaching institutions (.91 and .89). The RAMIs using the varying time windows, on the other hand, tend to be higher for the teaching institutions (e.g., 1.07 for major teaching hospitals; 0.99 for nonteaching hospitals).

The effects of the Medicare PPS on vulnerable subgroups of psychiatric patients treated in short-term general hospitals.

Changes in care in short-term general hospitals were monitored for three vulnerable subgroups of Medicare psychiatric patients: (1) those more than 75 years old, (2) those with comorbidities, and (3) those with one or more secondary diagnoses of psychiatric or substance abuse problems. Patterns of care studied for changes following institution of the Medicare Prospective Payment System (PPS) were volume of cases, average length of stay, discharge locations, and readmission rates. Results indicate that the changes occurring for the three subgroups were similar to the changes occurring for all Medicare psychiatric patients. After PPS was introduced in 1983, the average length of stay decreased, and a greater proportion of patients were discharged to other hospitals or home health care providers; however, rates of readmission to the same hospital did not increase.

Measuring hospital performance. The development and validation of risk-adjusted indexes of mortality, readmissions, and complications.

In this study we used information from discharge abstracts to develop three different risk-adjusted measures of hospital performance: a Risk-Adjusted Mortality Index, a Risk-Adjusted Readmissions Index, and a Risk-Adjusted Complications Index. The adjustments have face validity, and appear to account for much of the variation across hospitals in the rates of these adverse events. The indexes are stable over time, and are not biased with respect to hospital size, ownership, or teaching status. All three indexes appear to have construct validity when tested against the changes in hospital care that occurred when PPS was introduced.

How the medicare prospective payment system affects psychiatric patients treated in short-term general hospitals.

This study's purpose was to monitor changes in hospital utilization and discharge patterns for a large national sample of Medicare psychiatric patients treated in short-term general hospitals from 1980 through 1987. We compare data on the Medicare sample with trends for psychiatric patients with Blue Cross or private health insurance who were treated in the same hospitals. Study results indicate that treatment patterns changed for the Medicare psychiatric patients. Average length of stay decreased, especially for patients treated in scatterbeds. The proportion of patients discharged to other hospitals increased, and the number of admissions dropped for those patients over age 75.

The Risk-Adjusted Mortality Index. A new measure of hospital performance.

The Commission on Professional and Hospital Activities (CPHA) developed the Risk-Adjusted Mortality Index (RAMI), a method for comparing hospital death rates using existing abstract or billing data. The method is comprehensive insofar as it includes all payers and all types of cases except neonates. RAMI was designed to differentiate among admissions on the basis of the patient characteristics that increase or reduce the risk of dying in the hospital. Using a large national data base, risk factors were determined empirically within each of 310 clusters based on diagnosis-related groups (DRGs). The model was very effective at predicting risk-adjusted outcomes, with a correlation of 0.98 between actual and predicted deaths in a sample of 300 hospitals. RAMI appears to be a powerful tool for using existing data to monitor changes over time in hospital death rates.

Should DRG assignment be based on age?

The present Medicare Diagnosis Related Group (DRG) classification system contains 95 DRG pairs, where one DRG of the pair contains patients within a distinct diagnostic category who are under 70 years of age with no comorbidities or complications (CCs). The other DRG of the pair contains patients in the same diagnostic category who are over 69 or who have CCs. This study examines whether it is appropriate for reimbursement purposes to group those patients who are 70 years of age or older but have no CCs with patients who have CCs. Our findings show that age alone, in the absence of CCs, increases length of stay and cost of care only slightly. In fact, using only CCs as a classification variable reduces the within-group variance more than the present classification based on both age and CCs. Therefore, it is inappropriate to group Medicare patients who are older than 70 years of age without CCs with Medicare patients who have CCs.

The effect of PPS on hospital product and productivity.

The results suggest that Prospective Payment System (PPS) prompted a reduction in the proportion of Medicare patients that were discharged, for whom the hospital considered the episode of care to be completed. The results also show a reduction in the proportion of patients discharged dead. When controlling for patient type, the results support the findings, but the magnitude of the change that might be attributed to PPS is somewhat smaller. Proportional changes in the input measures for all patients were next considered. The results indicate that fewer diagnostic tests, fewer laboratory tests, and fewer x-rays were used in 1984. Laboratory tests showed the most dramatic decrease. LOS decreased, but the drug input remained fairly constant. A productivity index that reflects the change in the input measure while controlling for patient type was developed. The results provide strong evidence of a productivity increase in all products for Medicare patients. The drug input did not contribute to the productivity increase. The 50 most frequent DRGs for Medicare patients were examined separately for productivity changes by product. The results further support the findings of an increase in productivity.

Enrollment in and disenrollment from health maintenance organizations by Medicaid recipients.

In 1977-78 Medicaid recipients in Wayne County, Michigan had the option of joining health maintenance organizations (HMO's). This article presents an analysis of utilization levels and physician contact patterns prior to HMO enrollment and following HMO disenrollment. Medicaid families that had patterns of previous contacts with non-HMO physicians overwhelmingly choose the non-HMO option. Families with no physician contacts and very low utilization levels selected the HMO's. Also, higher than average utilization occurred during the 3 months following disenrollment from these HMO's.