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T P Hofer

Publications and source records attributed to T P Hofer.

At least 19 recordsLinked to original sources
PubMed2005

Barriers to following dietary recommendations in Type 2 diabetes.

AIMS: To evaluate barriers to following dietary recommendations in patients with Type 2 diabetes. METHODS: We conducted focus groups and surveys in urban and suburban VA and academic medical centres. For the written survey, a self-administered questionnaire was mailed to a random sample of 446 patients with diabetes. For the focus groups, six groups of patients with diabetes (three urban, three suburban) were conducted, with 6-12 participants in each group. The focus groups explored barriers across various types of diabetes self-management; we extracted all comments relevant to barriers that limited patients' ability to follow a recommended diet. RESULTS: The written survey measured the burden of diabetes therapies (on a seven-point rating scale). Moderate diet was seen as a greater burden than oral agents (median 1 vs. 0, P = 0.001), but less of a burden than insulin (median 1 vs. 4, P < 0.001). A strict diet aimed at weight loss was rated as being similarly burdensome to insulin (median 4 vs. 4, P = NS). Despite this, self-reported adherence was much higher for both pills and insulin than it was for a moderate diet. In the focus groups, the most commonly identified barrier was the cost (14/14 reviews), followed by small portion sizes (13/14 reviews), support and family issues (13/14 reviews), and quality of life and lifestyle issues (12/14 reviews). Patients in the urban site, who were predominantly African-American, noted greater difficulties communicating with their provider about diet and social circumstances, and also that the rigid schedule of a diabetes diet was problematic. CONCLUSIONS: Barriers to adherence to dietary therapies are numerous, but some, such as cost, and in the urban setting, communication with providers, are potentially remediable. Interventions aimed at improving patients' ability to modify their diet need to specifically address these areas. Furthermore, treatment guidelines need to consider patients' preferences and barriers when setting goals for treatment.

Diabetes Mellitus, Type 2↗
PubMed2004

Projections of demand and capacity for colonoscopy related to increasing rates of colorectal cancer screening in the United States.

BACKGROUND: There is debate about the optimal colorectal cancer screening test, partly because of concerns about colonoscopy demand. AIM: To quantify the demand for colonoscopy with different screening tests, and to estimate the ability of the United States health care system to meet demand. METHODS: We used a previously published Markov model and the United States census data to estimate colonoscopy demand. We then used an endoscopic database to compare current rates of screening-related colonoscopy with those projected by the model, and to estimate the number of endoscopists needed to meet colonoscopy demand. RESULTS: Annual demand for colonoscopy ranges from 2.21 to 7.96 million. Based on current practice patterns, demand exceeds current supply regardless of screening strategy. We estimate that an increase of at least 1360 gastroenterologists would be necessary to meet demand for colonoscopic screening undergone once at age 65, while colonoscopy every 10 years could require 32 700 more gastroenterologists. A system using dedicated endoscopists could meet demand with fewer endoscopists. CONCLUSIONS: Colorectal cancer screening leads to demand for colonoscopy that outstrips supply. Systems to train dedicated screening endoscopists may be necessary in order to provide population-wide screening. The costs and feasibility of establishing this infrastructure should be studied further.

Aged↗
PubMed2003

The measurement of active errors: methodological issues.

The value of research in any topic area turns on its validity. Patient safety research has revealed--or, at least, given renewed urgency to--a raft of methodological issues. The meaning and thus the value of empirical research in this field is contingent on getting the methodology right. The need for good methods for the measurement of error is necessary whenever an inference is intended and, since inferences lie at the heart of research and management, there is a huge need to understand better how to make measurements that are meaningful, precise, and accurate. In this paper we consider issues relating to the measurement of error and the need for more research.

Empirical Research↗
PubMed2001

Which colon cancer screening test? A comparison of costs, effectiveness, and compliance.

PURPOSE: Recent media reports have advocated the use of colonoscopy for colorectal cancer screening. However, colonoscopy is expensive compared with other screening modalities, such as fecal occult blood testing and flexible sigmoidoscopy. We sought to determine the cost effectiveness of different screening strategies for colorectal cancer at levels of compliance likely to be achieved in clinical practice. METHODS: A Markov decision model was used to examine screening strategies, including fecal occult blood testing alone, fecal occult blood testing combined with flexible sigmoidoscopy, flexible sigmoidoscopy alone, and colonoscopy. The timing and frequency of screening was varied to assess optimal screening intervals. Sensitivity analyses were conducted to assess the factors that have the greatest effect on the cost effectiveness of screening. RESULTS: All strategies are cost effective versus no screening, at less than $20,000 per life-year saved. Direct comparison suggests that the most effective strategies are twice-lifetime colonoscopy and flexible sigmoidoscopy combined with fecal occult blood testing. Assuming perfect compliance, flexible sigmoidoscopy combined with fecal occult blood testing is slightly more effective than twice-lifetime colonoscopy (at ages 50 and 60 years) but is substantially more expensive, with an incremental cost effectiveness of $390,000 per additional life-year saved. However, compliance with primary screening tests and colonoscopic follow-up for polyps affect screening decisions. Colonoscopy at ages 50 and 60 years is the preferred test regardless of compliance with the primary screening test. However, if follow-up colonoscopy for polyps is less than 75%, then even once-lifetime colonoscopy is preferred over most combinations of flexible sigmoidoscopy and fecal occult blood testing. Costs of colonoscopy and proportion of cancer arising from polyps also affect cost effectiveness. CONCLUSIONS: Colonoscopic screening for colorectal cancer appears preferable to current screening recommendations. Screening recommendations should be tailored to the compliance levels achievable in different practice settings.

Aged↗
PubMed2001

Estimating hospital deaths due to medical errors: preventability is in the eye of the reviewer.

CONTEXT: Studies using physician implicit review have suggested that the number of deaths due to medical errors in US hospitals is extremely high. However, some have questioned the validity of these estimates. OBJECTIVE: To examine the reliability of reviewer ratings of medical error and the implications of a death described as "preventable by better care" in terms of the probability of immediate and short-term survival if care had been optimal. DESIGN: Retrospective implicit review of medical records from 1995-1996. SETTING AND PARTICIPANTS: Fourteen board-certified, trained internists used a previously tested structured implicit review instrument to conduct 383 reviews of 111 hospital deaths at 7 Department of Veterans Affairs medical centers, oversampling for markers previously found to be associated with high rates of preventable deaths. Patients considered terminally ill who received comfort care only were excluded. MAIN OUTCOME MEASURES: Reviewer estimates of whether deaths could have been prevented by optimal care (rated on a 5-point scale) and of the probability that patients would have lived to discharge or for 3 months or more if care had been optimal (rated from 0%-100%). RESULTS: Similar to previous studies, almost a quarter (22.7%) of active-care patient deaths were rated as at least possibly preventable by optimal care, with 6.0% rated as probably or definitely preventable. Interrater reliability for these ratings was also similar to previous studies (0.34 for 2 reviewers). The reviewers' estimates of the percentage of patients who would have left the hospital alive had optimal care been provided was 6.0% (95% confidence interval [CI], 3.4%-8.6%). However, after considering 3-month prognosis and adjusting for the variability and skewness of reviewers' ratings, clinicians estimated that only 0.5% (95% CI, 0.3%-0.7%) of patients who died would have lived 3 months or more in good cognitive health if care had been optimal, representing roughly 1 patient per 10 000 admissions to the study hospitals. CONCLUSIONS: Medical errors are a major concern regardless of patients' life expectancies, but our study suggests that previous interpretations of medical error statistics are probably misleading. Our data place the estimates of preventable deaths in context, pointing out the limitations of this means of identifying medical errors and assessing their potential implications for patient outcomes.

Bias↗
PubMed2001

The role of hospital volume in coronary artery bypass grafting: is more always better?

OBJECTIVES: The goal of this study was to determine whether outcomes of nonemergent coronary artery bypass grafting (CABG) differed between low- and high-volume hospitals in patients at different levels of surgical risk. BACKGROUND: Regionalizing all CABG surgeries from low- to high-volume hospitals could improve surgical outcomes but reduce patient access and choice. "Targeted" regionalization could be a reasonable alternative, however, if subgroups of patients that would clearly benefit from care at high-volume hospitals could be identified. METHODS: We assessed outcomes of CABG at 56 U.S. hospitals using 1997 administrative and clinical data from Solucient EXPLORE, a national outcomes benchmarking database. Predicted in-hospital mortality rates for subjects were calculated using a logistic regression model, and subjects were classified into five groups based on surgical risk: minimal (< 0.5%), low (0.5% to 2%), moderate (2% to 5%), high (5% to 20%), and severe (> or =20%). We assessed differences in in-hospital mortality, hospital costs and length of stay between low- and high-volume facilities (defined as > or =200 annual cases) in each of the five risk groups. RESULTS: A total of 2,029 subjects who underwent CABG at 25 low-volume hospitals and 11,615 subjects who underwent CABG at 31 high-volume hospitals were identified. Significant differences in in-hospital mortality were seen between low- and high-volume facilities in subjects at moderate (5.3% vs. 2.2%; p = 0.007) and high risk (22.6% vs. 11.9%; p = 0.0026) but not in those at minimal, low or severe risk. Hospital costs and lengths of stay were similar across each of the five risk groups. Based on these results, targeted regionalization of subjects at moderate risk or higher to high-volume hospitals would have resulted in an estimated 370 transfers and avoided 16 deaths; in contrast, full regionalization would have led to 2,029 transfers and avoided 20 deaths. CONCLUSIONS: Targeted regionalization might be a feasible strategy for balancing the clinical benefits of regionalization with patients' desires for choice and access.

Adult↗
PubMed2001

Who bounces back? Physiologic and other predictors of intensive care unit readmission.

OBJECTIVE: To determine the influence of changes in acute physiology scores (APS) and other patient characteristics on predicting intensive care unit (ICU) readmission. DESIGN: Secondary analysis of a prospective cohort study. SETTING: Single large university medical intensive care unit. PATIENTS: A total of 4,684 consecutive admissions from January 1, 1994, to April 1, 1998, to the medical ICU. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The independent influence of patient characteristics, including daily APS, admission diagnosis, treatment status, and admission location, on ICU readmission was evaluated using logistic regression. After accounting for first ICU admission deaths, 3,310 patients were "at-risk" for ICU readmission and 317 were readmitted (9.6%). Hospital mortality was five times higher (43% vs. 8%; p < .0001), and length of stay was two times longer (16 +/- 16 vs. 32 +/- 28 days; p < .001) in readmitted patients. Mean discharge APS was significantly higher in the readmitted group compared with the not readmitted group (43 +/- 19 vs. 34 +/- 18; p > .01). Significant independent predictors of ICU readmission included discharge APS >40 (odds ratio [OR] 2.1; 95% confidence interval [CI] 1.6-2.7; p < .0001), admission to the ICU from a general medicine ward (Floor) (OR 1.9; 95% CI 1.4-2.6; p < .0001), and transfer to the ICU from other hospital (Transfer) (OR 1.7; 95% CI 1.3-2.3; p < .01). The overall model calibration and discrimination were (H-L chi2 = 3.8, df = 8; p = .85) and (receiver operating characteristic 0.67), respectively. CONCLUSIONS: Patients readmitted to medical ICUs have significantly higher hospital lengths of stay and mortality. ICU readmissions may be more common among patients who respond poorly to treatment as measured by increased severity of illness at first ICU discharge and failure of prior therapy at another hospital or on a general medicine unit. Tertiary care ICUs may have higher than expected readmission rates and mortalities, even when accounting for severity of illness, if they care for significant numbers of transferred patients.

APACHE↗
PubMed2001

Avoiding pitfalls in chronic disease quality measurement: a case for the next generation of technical quality measures.

The true utility of quality measurement lies in its ability to inspire quality improvement, with resultant enhancements in the processes and outcomes of care. Because quality measurement is expensive, it is difficult to justify using measures that are not likely to lead to important improvements in health. Many current measures of chronic disease technical quality, however, have one or more pitfalls that prevent them from motivating quality improvement reactions. These pitfalls include that: (1) measured processes of care lack strong links to outcomes; (2) actionable processes of care are not measured; (3) measures do not target those at highest risk; (4) measures do not allow for patient exceptions; and (5) intermediate outcome measures are not severity adjusted. To exemplify recent advancements and current pitfalls in chronic disease quality measurement, we examine the evolution of quality measures for diabetes mellitus and discuss the limitations of many currently used diabetes mellitus care measures. We then propose more clinically meaningful "tightly linked" measures that examine clinical processes directly linked to outcomes, target populations with specific diagnoses or intermediate disease outcomes that contribute to risk for poor downstream health outcomes, and explicitly incorporate exceptions. We believe that using more tightly linked measures in quality assessment will identify important quality of care problems and is more likely to produce improved outcomes for those with chronic diseases.

Chronic Disease↗
PubMed2000

Are physicians aware of which of their patients have indwelling urinary catheters?

PURPOSE: Although infections associated with indwelling urinary catheters are common, costly, and morbid, the use of these catheters is unnecessary in more than one-third of patients. We sought to assess whether attending physicians, medical residents, and medical students are aware if their hospitalized patients have an indwelling urinary catheter, and whether physician awareness is associated with appropriate use of these catheters. METHODS: The physicians and medical students responsible for patients admitted to the medical services at four university-affiliated hospitals were given a list of the patients on their service. For each patient, the provider was asked: "As of yesterday afternoon, did this patient have an indwelling urethral catheter?" Respondents' answers were compared with the results of examining the patient. RESULTS: Among 288 physicians and students on 56 medical teams, 256 (89%) completed the survey. Of 469 patients, 117 (25%) had an indwelling catheter. There were a total of 319 provider-patient observations among these 117 patients. Overall, providers were unaware of catheterization for 88 (28%) of the 319 provider-patient observations. Unawareness rates by level of training were 21% for students, 22% for interns, 27% for residents, and 38% for attending physicians (P = 0.06). Catheter use was inappropriate in 36 (31%) of the 117 patients with a catheter. Providers were unaware of catheter use for 44 (41%) of the 108 provider-patient observations of patients who were inappropriately catheterized. Catheterization was more likely to be appropriate if respondents were aware of the catheter (odds ratio = 3.7; 95% confidence interval, 2.1 to 6.7, P <0.001). CONCLUSION: Physicians are commonly unaware that their patients have an indwelling urinary catheter. Inappropriate catheters are more often "forgotten" than appropriate ones. System-wide interventions aimed at discontinuing unnecessary catheterization seem warranted.

Aged↗
PubMed2000

Cost-utility analysis of screening intervals for diabetic retinopathy in patients with type 2 diabetes mellitus.

CONTEXT: Annual eye screening for patients with diabetes mellitus is frequently proposed as a measure of quality of care. However, the benefit of annual vs less frequent screening intervals has not been well evaluated, especially for low-risk patients. OBJECTIVE: To examine the marginal cost-effectiveness of various screening intervals for eye disease in patients with type 2 diabetes, stratified by age and level of glycemic control. DESIGN: Markov cost-effectiveness model. SETTING AND PARTICIPANTS: Hypothetical patients based on the US population of diabetic patients older than 40 years from the Third National Health and Nutrition Examination Survey. MAIN OUTCOME MEASURES: Patient time spent blind, quality-adjusted life-years (QALYs), and costs of annual vs less frequent screening compared by age and level of hemoglobin A1c. RESULTS: Retinal screening in patients with type 2 diabetes is an effective intervention; however, the risk reduction varies dramatically by age and level of glycemic control. On average, a high-risk patient who is aged 45 years and has a hemoglobin A1c level of 11% gains 21 days of sight when screened annually as opposed to every third year, while a low-risk patient who is aged 65 years and has a hemoglobin A1c level of 7% gains an average of 3 days of sight. The marginal cost-effectiveness of screening annually vs every other year also varies; patients in the high-risk group cost an additional $40530 per QALY gained, while those in the low-risk group cost an additional $211570 per QALY gained. In the US population, retinal screening annually vs every other year for patients with type 2 diabetes costs $107510 per QALY gained, while screening every other year vs every third year costs $49760 per QALY gained. CONCLUSIONS: Annual retinal screening for all patients with type 2 diabetes without previously detected retinopathy may not be warranted on the basis of cost-effectiveness, and tailoring recommendations to individual circumstances may be preferable. Organizations evaluating quality of care should consider costs and benefits carefully before setting universal standards.

Adult↗
PubMed2000

Estimating the microvascular benefits of screening for type 2 diabetes mellitus.

OBJECTIVE: To define the relative benefits of screening for diabetes and improved treatment programs and ways of improving the efficiency of screening for a population-based cohort derived from the Third National Health and Nutrition Examination Survey (NHANES III). METHODS: A Markov decision model is used to estimate microvascular benefits of glucose control for four different screening and treatment scenarios, including either universal screening or improved glucose control of known diabetic subjects, neither, or both. RESULTS: A population cohort of subjects with recent onset of diabetes (< 5 years) was derived from NHANES III (of whom close to half were unaware that they had diabetes). In this population-based cohort, the total benefit achievable by universal screening and improved treatment (limiting HbA1c to less than 9%) is a reduction of about 30,000 cases of blindness over the lifetime of the cohort. Screening alone results in 7% of this benefit, and improved treatment alone provides 65%. Screening a targeted group of patients with three or more risk factors for developing diabetes would reduce the number of required fasting glucose measurements needed by 82% and provide 50% of the total benefit of screening the entire population with a fasting glucose measurement. CONCLUSIONS: Morbidity from type 2 diabetes can be most effectively reduced by developing ways to modestly improve the glycemic control of known diabetic subjects, particularly those with high A1c's and early onset of disease. Targeting can significantly reduce the number of persons who need to be screened with a fasting blood test while preserving a large component of the benefit of screening.

Blindness↗
PubMed2000

Automated computerized intensive care unit severity of illness measure in the Department of Veterans Affairs: preliminary results. SISVistA Investigators. Scrutiny of ICU Severity Veterans Health Sysyems Technology Architecture.

OBJECTIVE: To evaluate the feasibility of an automated intensive care unit (ICU) risk adjustment tool (acronym: SISVistA) developed by selecting a subset of predictor variables from the Acute Physiology and Chronic Health Evaluation (APACHE) III available in the existing computerized database of the Department of Veterans Affairs (VA) healthcare system and modifying the APACHE diagnostic and comorbidity approach. DESIGN: Retrospective cohort study. SETTING: Six ICUs in three Ohio Veterans Affairs hospitals. PATIENT SELECTION: The first ICU admission of all patients from February 1996 through July 1997. OUTCOME MEASURE: Mortality at hospital discharge. METHODS: The predictor variables, including age, comorbidity, diagnosis, admission source (direct or transfer), and laboratory results (from the +/- 24-hr period surrounding admission), were extracted from computerized VA databases, and APACHE III weights were applied using customized software. The weights of all laboratory variables were added and treated as a single variable in the model. A logistic regression model was fitted to predict the outcome and the model was validated using a boot-strapping technique (1,000 repetitions). MAIN RESULTS: The analysis included all 4,651 eligible cases (442 deaths). The cohort was predominantly male (97.5%) and elderly (63.6 +/- 12.0 yrs). In multivariate analysis, significant predictors of hospital mortality included age (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.04-1.09), comorbidity (OR, 1.11; 95% CI, 1.08-1.15), total laboratory score (OR, 1.07; 95% CI, 1.06-1.08), direct ICU admission (OR, 0.39; 95% CI, 0.31-0.49), and several broad ICU diagnostic categories. The SISVistA model had excellent discrimination and calibration (C statistic = 0.86, goodness-of-fit statistics; p > .20). The area under the receiver operating characteristic curve of the validated model was 0.86. CONCLUSIONS: Using common data elements often found in hospital computer systems, SISVistA predicts hospital mortality among patients in Ohio VA ICUs. This preliminary study supports the development of an automated ICU risk prediction system on a more diverse population.

APACHE↗
PubMed2000

Discussion between reviewers does not improve reliability of peer review of hospital quality.

OBJECTIVES: Peer review is used to make final judgments about quality of care in many quality assurance activities. To overcome the low reliability of peer review, discussion between several reviewers is often recommended to point out overlooked information or allow for reconsideration of opinions and thus improve reliability. The authors assessed the impact of discussion between 2 reviewers on the reliability of peer review. METHODS: A group of 13 board-certified physicians completed a total of 741 structured implicit record reviews of 95 records for patients who experienced severe adverse events related to laboratory abnormalities while in the hospital (hypokalemia, hyperkalemia, renal failure, hyponatremia, and digoxin toxicity). They independently assessed the degree to which each adverse event was caused by medical care and the quality of the care leading up to the adverse event. Working in pairs, they then discussed differences of opinion, clarified factual discrepancies, and rerated the record. The authors compared the reliability of each measure before and after discussion, and between and within pairs of reviewers, using the intraclass correlation coefficient for continuous ratings and the kappa statistic for a dichotomized rating. RESULTS: The assessment of whether the laboratory abnormality was iatrogenic had a reliability of 0.46 before discussion and 0.71 after discussion between paired reviewers, indicating considerably improved agreement between the members of a pair. However, across reviewer pairs, the reviewer reliability was 0.36 before discussion and 0.40 after discussion. Similarly, for the rating of overall quality of care, reliability of physician review went from 0.35 before discussion to 0.58 after discussion as assessed by pair. However, across pairs the reliability increased only from 0.14 to 0.17. Even for prediscussion ratings, reliability was substantially higher between 2 members of a pair than across pairs, suggesting that reviewers who work in pairs learn to be more consistent with each other even before discussion, but this consistency also did not improve overall reliability across pairs. CONCLUSIONS: When 2 physicians discuss a record that they are reviewing, it substantially improves the agreement between those 2 physicians. However, this improvement is illusory, as discussion does not improve the overall reliability as assessed by examining the reliability between physicians who were part of different discussions. This finding may also have implications with regard to how disagreements are resolved on consensus panels, guideline committees, and reviews of literature quality for meta-analyses.

Causality↗
PubMed2000

Breast cancer screening in the United States and Canada, 1994: socioeconomic gradients persist.

OBJECTIVES: This study compared rates of annual mammography screening across socioeconomic status between the United States and Canada in 1994. METHODS: Population-based cross-sectional surveys were used to compare the rates. RESULTS: Screening rates were higher in the United States than in Canada for women aged 50 to 69 years (47.3% vs 38.8%; P < .01). Women with higher education and with higher incomes were more likely to receive screening in both countries, with no significant differences between countries. CONCLUSIONS: For women aged 50 to 69 years, screening rates in Canada have substantially increased relative to those in the United States. However, disparities in screening across levels of socioeconomic status persist in both countries.

Age Factors↗
PubMed1999

The unreliability of individual physician "report cards" for assessing the costs and quality of care of a chronic disease.

CONTEXT: Physician profiling is widely used by many health care systems, but little is known about the reliability of commonly used profiling systems. OBJECTIVES: To determine the reliability of a set of physician performance measures for diabetes care, one of the most common conditions in medical practice, and to examine whether physicians could substantially improve their profiles by preferential patient selection. DESIGN AND SETTING: Cohort study performed from 1990 to 1993 at 3 geographically and organizationally diverse sites, including a large staff-model health maintenance organization, an urban university teaching clinic, and a group of private-practice physicians in an urban area. PARTICIPANTS: A total of 3642 patients with type 2 diabetes cared for by 232 different physicians. MAIN OUTCOME MEASURES: Physician profiles for their patients' hospitalization and clinic visit rates, total laboratory resource utilization rate and level of glycemic control by average hemoglobin A1c level with and without detailed case-mix adjustment. RESULTS: For profiles based on hospitalization rates, visit rates, laboratory utilization rates, and glycemic control, 4% or less of the overall variance was attributable to differences in physician practice and the reliability of the median physician's case-mix-adjusted profile was never better than 0.40. At this low level of physician effect, a physician would need to have more than 100 patients with diabetes in a panel for profiles to have a reliability of 0.80 or better (while more than 90% of all primary care physicians at the health maintenance organization had fewer than 60 patients with diabetes). For profiles of glycemic control, high outlier physicians could dramatically improve their physician profile simply by pruning from their panel the 1 to 3 patients with the highest hemoglobin A1c levels during the prior year. This advantage from gaming could not be prevented by even detailed case-mix adjustment. CONCLUSIONS: Physician "report cards" for diabetes, one of the highest-prevalence conditions in medical practice, were unable to detect reliably true practice differences within the 3 sites studied. Use of individual physician profiles may foster an environment in which physicians can most easily avoid being penalized by avoiding or deselecting patients with high prior cost, poor adherence, or response to treatments.

Benchmarking↗
PubMed1999

Accuracy of risk-adjusted mortality rate as a measure of hospital quality of care.

OBJECTIVES: Reports on hospital quality performance are being produced with increasing frequency by state agencies, commercial data vendors, and health care purchasers. Risk-adjusted mortality rate is the most commonly used measure of quality in these reports. The purpose of this study was to determine whether risk-adjusted mortality rates are valid indicators of hospital quality performance. METHODS: Based on an analytical model of random measurement error, sensitivity and predictive error of mortality rate indicators of hospital performance were estimated. RESULTS: The following six parameters were shown to determine accuracy: (1) mortality risks of patients who receive good quality care and (2) of those who receive poor quality care, (3) proportion of patients (across all hospitals) who receive poor quality care, (4) proportion of hospitals considered to be "poor quality," (5) patients' relative risk of receiving poor quality care in "good quality" and in "poor quality" hospitals, and (6) number of patients treated per hospital. Using best available values for model parameters, analyses demonstrated that in nearly all situations, even with perfect risk adjustment, identifying poor quality hospitals on the basis of mortality rate performance is highly inaccurate. Of hospitals that delivered poor quality care, fewer than 12% were identified as high mortality rate outliers, and more than 60% of outliers were actually good quality hospitals. CONCLUSIONS: Under virtually all realistic assumptions for model parameter values, sensitivity was less than 20% and predictive error was greater than 50%. Reports that measure quality using risk-adjusted mortality rates misinform the public about hospital performance.

Bias↗