Severity-adjusted Mortality Research Articles

Judging hospitals by severity-adjusted mortality rates: the influence of the severity-adjustment method.

This research examined whether judgments about a hospital's risk-adjusted mortality performance are affected by the severity-adjustment method. Data came from 100 acute care hospitals nationwide and 11880 adults admitted in 1991 for acute myocardial infarction. Ten severity measures were used in separate multivariable logistic models predicting in-hospital death. Observed-to-expected death rates and z scores were calculated with each severity measure for each hospital. Unadjusted mortality rates for the 100 hospitals ranged from 4.8% to 26.4%. For 32 hospitals, observed mortality rates differed significantly from expected rates for 1 or more, but not for all 10, severity measures. Agreement between pairs of severity measures on whether hospitals were flagged as statistical mortality outliers ranged from fair to good. Severity measures based on medical records frequently disagreed with measures based on discharge abstracts. Although the 10 severity measures agreed about relative hospital performance more often than would be expected by chance, assessments of individual hospital mortality rates varied by different severity-adjustment methods.

Critical care outcomes: linking structures, processes, and organizational and clinical outcomes

Organizational structure and process are thought to affect patient care outcomes beyond the effects of expert clinical care. To test the hypothesis that a discretionary pattern of organizational structure and process factors is predictive of critical care unit performance, ie, desirable patient and organizational outcomes. Quality-of-care patient and organizational outcomes were evaluated in 25 critical care units. A single value representing each critical care unit's euclidian distance from a theoretically ideal pattern of discretionary function was determined and correlated with unit-level measures of outcomes (standardized mortality ratio, severity-adjusted length of stay, patient satisfaction, quality of nursing care, and nursing retention). Distance from the ideal-type discretionary pattern predicted organizational but not clinical outcomes. Units closer to the ideal-type pattern had higher RN retention, and were viewed as better places to work, with higher-quality care by both nurses and physicians. Objectively measured quality of care, patient satisfaction, severity-adjusted mortality, and length of stay were not consistently related to better-structured units. With experienced critical care practitioners, unit-level structure and process factors were better predictors of organizational outcomes than of clinical outcomes.

Impact of Quality-of-Care Factors on Pediatric Intensive Care Unit Mortality

To determine the importance of the following care factors previously associated with hospital quality on survival from pediatric intensive care: size of the intensive care unit (ICU), medical school teaching status of the hospital housing the ICU, specialist status (pediatric intensivist), and unit coordination. After a national survey, consecutive case series were collected at 16 sites randomly selected to represent unique combinations of quality-of-care factors. Pediatric ICUs. Consecutive admissions to each site. Patient mortality adjusted for physiologic status, diagnosis, and other mortality risk factors. There were 5415 pediatric ICU admissions and 248 ICU deaths. The ICUs differed significantly with respect to descriptive variables, including mortality (range, 2.2% to 16.4%). Analysis of risk-adjusted mortality indicated that the hospital teaching status and the presence of a pediatric intensivist were significantly associated with a patient's chance of survival. The probability of patient survival after hospitalization in an ICU located in a teaching hospital was decreased (relative odds of dying, 1.79; 95% confidence interval [CI], 1.23 to 2.61; P = .002). In contrast, the probability of patient survival after hospitalization in an ICU with a pediatric intensivist was improved (relative odds of dying, 0.65; 95% CI, 0.44 to 0.95; P = .027). Post hoc analysis indicated that the higher severity-adjusted mortality in teaching hospitals may be explained by the presence of residents caring for ICU patients. Characteristics indicative of the best overall hospital quality may not be associated, or may be negatively associated, with quality of care in specialized care areas, including the pediatric ICU.