Patients' values for health states associated with hepatitis C and physicians' estimates of those values.

OBJECTIVES: Hepatitis C is the leading cause of chronic hepatitis in the United States. Little information is available regarding how persons with hepatitis C view health with their disease. We studied patients' perceptions about the value of hepatitis C health states and evaluated whether physicians understand their patients' perspectives about this disease. METHODS: A total of 50 consecutive persons with hepatitis C were surveyed when they presented as new patients to a hepatology practice. Subjects provided utility assessments (preference values) for five hepatitis C health states and for treatment side effects. They also stated their threshold for accepting antiviral therapy. Five hepatologists used the same scales to estimate their patients' responses. RESULTS: On average, patients believed that hepatitis C without symptoms was associated with an 11% reduction in preference value from that of life without infection, and the most serious condition (severe symptoms, cirrhosis) was believed to carry a 73% decrement. Patients judged the side effects of antiviral therapy quite unfavorably, and their median stated threshold for accepting treatment was a cure rate of 80%. Physicians' estimates were not significantly associated with patients' preference values for hepatitis C health states, treatment side effects, or with patients' thresholds for accepting treatment. In multivariate analysis, patients' stated thresholds for taking treatment were significantly associated with their decisions regarding therapy (beta = -2.72+/-1.21, p = 0.025). CONCLUSIONS: There was little agreement between patients' preference values about hepatitis C and their physicians' estimates of those values. Utility analysis could facilitate shared decision making about hepatitis C.

Physicians' preference values for hepatitis C health states and antiviral therapy: a survey.

BACKGROUND: Physicians' perspectives regarding hepatitis C shape their approach to patient management. We used utility analysis to evaluate physicians' perceptions of hepatitis C-related health states (HS) and their threshold to recommend treatment. METHODS: A written questionnaire was administered to practicing physicians. They were asked to rate hepatitis C health states on a visual analog scale ranging from 0% (death) to 100% (health without hepatitis C). Physicians then judged quality of life associated with the side effects of antiviral therapy for hepatitis C and indicated the sustained virological response rate that they would require to recommend treatment. RESULTS: One hundred and thirteen physicians from five states were included. Median utility ratings for hepatitis C health states declined significantly with increasing severity of symptoms: HS1-No Symptoms, No Cirrhosis (88%; 12% reduction from good health), HS2-Mild Symptoms, No Cirrhosis (66%), HS3-Moderate Symptoms, No Cirrhosis (49%), HS4-Mild Symptoms, Cirrhosis (40%), HS5-Severe Symptoms, Cirrhosis (18%) [p < 0.001]. The median rating for life with side effects of antiviral therapy was 47%, suggesting a 53% reduction from good health. That was similar to the utility value for HS3-Moderate Symptoms, No Cirrhosis. The median threshold value for recommending treatment was a sustained response rate of 60%. CONCLUSIONS: 1) Physicians' utility ratings for hepatitis C health states were inversely related to the severity of disease manifestations described. 2) Physicians viewed side effects of therapy unfavorably and indicated that on average, they would require a 60% sustained response rate before recommending treatment, which far exceeds the efficacy of current antiviral therapy for hepatitis C in the majority of patients.

Finding cancer in primary care outpatients with low back pain: a comparison of diagnostic strategies.

OBJECTIVE: To compare strategies for diagnosing cancer in primary care patients with low back pain. Strategies differed in their use of clinical findings, erythrocyte sedimentation rate (ESR), and plain x-rays prior to imaging and biopsy. DESIGN: Decision analysis and cost effectiveness analysis with sensitivity analyses. Strategies were compared in terms of sensitivity, specificity, and diagnostic cost effectiveness ratios. SETTING: Hypothetical MEASUREMENTS: Estimates of disease prevalence and test characteristics were taken from the literature. Costs were represented by the Medicare reimbursement for the tests and procedures employed. MAIN RESULTS: In the baseline analysis, using magnetic resonance imaging (MRI) as the imaging procedure prior to a single biopsy, strategies ranged in sensitivity from 0.40 to 0.73, with corresponding diagnostic costs of $14 to $241 per patient and average cost effectiveness ratios of $5,283 to $49,814 per case of cancer found. Incremental cost effectiveness ratios varied from $8,397 to $624,781; 5 strategies were dominant in the baseline analysis. Use of a higher ESR cutoff point (50 mm/hr) improved specificity and cost effectiveness for certain strategies. Imaging with MRI, or bone scan followed in series by MRI, resulted in a fewer unnecessary biopsies than imaging with bone scan alone. Cancer prevalence was an important determinant of cost effectiveness. CONCLUSIONS: We recommend a strategy of imaging patients who have a clinical finding (history of cancer, age > or = 50 years, weight loss, or failure to improve with conservative therapy) in combination with either an elevated ESR (> 50 mm/hr) or a positive x-ray, or using the same approach but imaging directly those patients with a history of cancer.

Teaching residents evidence-based medicine skills: a controlled trial of effectiveness and assessment of durability.

OBJECTIVES: To measure the effectiveness of an educational intervention designed to teach residents four essential evidence-based medicine (EBM) skills: question formulation, literature searching, understanding quantitative outcomes, and critical appraisal. DESIGN: Firm-based, controlled trial. SETTING: Urban public hospital. PARTICIPANTS: Fifty-five first-year internal medicine residents: 18 in the experimental group and 37 in the control group. INTERVENTION: An EBM course, taught 2 hours per week for 7 consecutive weeks by senior faculty and chief residents focusing on the four essential EBM skills. MEASUREMENTS AND MAIN RESULTS: The main outcome measure was performance on an EBM skills test that was administered four times over 11 months: at baseline and at three time points postcourse. Postcourse test 1 assessed the effectiveness of the intervention in the experimental group (primary outcome]; postcourse test 2 assessed the control group after it crossed over to receive the intervention; and postcourse test 3 assessed durability. Baseline EBM skills were similar in the two groups. After receiving the EBM course, the experimental group achieved significantly higher postcourse test scores (adjusted mean difference, 21%; 95% confidence interval, 13% to 28%; P < .001). Postcourse improvements were noted in three of the four EBM skill domains (formulating questions, searching, and quantitative understanding [P < .005 for all], but not in critical appraisal skills [P = .4]). After crossing over to receive the educational intervention, the control group achieved similar improvements. Both groups sustained these improvements over 6 to 9 months of follow-up. CONCLUSIONS: A brief structured educational intervention produced substantial and durable improvements in residents' cognitive and technical EBM skills.

Use of the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI) to assist with triage of patients with chest pain or other symptoms suggestive of acute cardiac ischemia. A multicenter, controlled clinical trial.

BACKGROUND: Approximately 6 million U.S. patients present to emergency departments annually with symptoms suggesting acute cardiac ischemia. Triage decisions for these patients are important but remain difficult. OBJECTIVE: To test whether computerized prediction of the probability of acute ischemia, used with electrocardiography, improves the accuracy of triage decisions. DESIGN: Controlled clinical trial. SETTING: 10 hospital emergency departments in the midwestern, southeastern, and northeastern United States. PATIENTS: 10689 patients with chest pain or other symptoms suggestive of acute cardiac ischemia. INTERVENTION: The probability of acute ischemia predicted by the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI), either automatically printed or not printed on patients' electrocardiograms. MEASUREMENTS: Emergency department triage to a coronary care unit (CCU), telemetry unit, ward, or home. Other measurements were the bed capacity of the CCU relative to that of the telemetry unit; training or supervision status of the triaging physician; and patient diagnoses and outcomes based on clinical, electrocardiographic, and creatine kinase data. RESULTS: For patients without cardiac ischemia, in hospitals with high-capacity CCUs and relatively low-capacity cardiac telemetry units, use of ACI-TIPI was associated with a reduction in CCU admissions from 15% to 12%, a change of -16% (95% CI, -30% to 0%), and an increase in emergency department discharges to home from 49% to 52%, a change of 6% (CI, 0% to 14%; overall P=0.09). Across all hospitals, for patients evaluated by unsupervised residents, use of ACI-TIPI was associated with a reduction in CCU admissions from 14% to 10%, a change of -32% (CI, -55% to 3%); a reduction in telemetry unit admissions from 39% to 31%, a change of -20% (CI, -34% to -2%); and an increase in discharges to home from 45% to 56%, a change of 25% (CI, 8% to 45%; overall P=0.008). Among patients with stable angina, in hospitals with high-capacity CCUs, use of ACI-TIPI was associated with a reduction in CCU admissions from 26% to 13%, a change of -50% (CI, -70% to -17%), and an increase in discharges to home from 20% to 22%, a change of 10% (CI, -29% to 71%; overall P=0.02). At hospitals with high-capacity telemetry units, use of ACI-TIPI was associated with a reduction in telemetry unit admissions from 68% to 59%, a change of -14% (CI, -27% to 1%), and an increase in emergency department discharges to home from 10% to 21%, a change of 100% (CI, 22% to 230%; overall P=0.02). Among patients with acute myocardial infarction or unstable angina, use of ACI-TIPI did not change appropriate admission (96%) to the CCU or telemetry unit at hospitals with high-capacity CCUs or telemetry units. CONCLUSIONS: Use of ACI-TIPI was associated with reduced hospitalization among emergency department patients without acute cardiac ischemia. This result varied as expected according to the CCU and cardiac telemetry unit capacities and physician supervision at individual hospitals. Appropriate admission for unstable angina or acute infarction was not affected. If ACI-TIPI is used widely in the United States, its potential incremental impact may be more than 200000 fewer unnecessary hospitalizations and more than 100000 fewer unnecessary CCU admissions.

Acute severe low back pain. A population-based study of prevalence and care-seeking.

STUDY DESIGN: Telephone interviews were conducted with a random sample of adults in 4437 North Carolina households. The response rate was 79%. OBJECTIVE: The prevalence of low back pain and the correlates of care-seeking in a defined population were examined. SUMMARY OF BACKGROUND DATA: Previous research on low back pain has used varying definitions of the illness of low back pain, and has admixed patients with acute and chronic low back pain. Acute low back pain was examined in this study as a distinct phenomenon separate from chronic low back pain. METHODS: Respondents completed a detailed interview regarding the occurrence of and care sought for back pain in 1991. Acute back pain was defined as functionally limiting pain lasting less than 3 months. RESULTS: From this sample, 485 individuals had at least one occurrence of acute severe low back pain in 1991, representing 7.6% of the adult population. Symptoms were reported less commonly in individuals older than age 60 years (5% vs. 8.5%) and in nonwhites compared with whites (5% vs. 8.5%). Thirty-nine percent of those with back pain sought medical care; 24% sought care initially from an allopathic physician, 13% from a chiropractor, and 2% from other providers. More prolonged pain, more severe pain, and sciatica were associated with care-seeking. Gender, income, age, rural residence, and health insurance status did not correlate with the decision to seek medical care. Younger age, male gender, and nonjob-related pain did correlate with the decision to seek care from a chiropractor. CONCLUSIONS: Acute back pain is common. Care is often sought regardless of income and insurance status. Seeing a health care provider for acute back pain may not be discretionary from the perspective of the patient.

A decision analysis of streptokinase plus heparin as compared with heparin alone for deep-vein thrombosis.

BACKGROUND: It is uncertain whether patients with proximal deep-vein thrombosis should be treated with streptokinase followed by intravenous heparin or with intravenous heparin alone. Published reports indicate that streptokinase plus heparin increases the risk of bleeding, including central nervous system bleeding and death, but decreases the risk of postphlebitic syndrome. Previous recommendations regarding these treatments have not considered patients' preferences or the values they attach to the possible outcomes of therapy. METHODS: We used decision analysis to combine published estimates of the probabilities of various adverse outcomes of treatment (bleeding, pulmonary embolism, postphlebitic syndrome, and death) with the values patients placed on these outcomes. We questioned 36 patients about the values they attached to each outcome. Sixteen patients had had deep-vein thrombosis, and 20 had not. RESULTS: By the values they attached to the outcomes, all 36 patients indicated that they were unwilling to accept an increased risk of death to avoid postphlebitic syndrome. According to the decision analysis, heparin alone was the better treatment for all 36 patients. As compared with streptokinase plus heparin, heparin alone provided 29 days of additional life expectancy over the predicted life expectancy of 20 years. Although the difference between the two treatments was small, heparin alone remained the better treatment in sensitivity analyses that examined the reasonable ranges of probabilities of the clinical outcomes. CONCLUSIONS: The values patients placed on the outcomes of treatment for deep-vein thrombosis support the use of heparin alone over the combined use of streptokinase and heparin.

The characteristics of peer reviewers who produce good-quality reviews.

OBJECTIVE: To determine the characteristics of good peer reviewers. DESIGN: Cross-sectional analysis of data gathered during a randomized controlled trial. SETTING: The Journal of General Internal Medicine. PARTICIPANTS: 226 reviewers of 131 consecutively submitted manuscripts of original research. 201 (91%) completed the review and submitted a curriculum vitae. MEASUREMENTS AND MAIN RESULTS: The quality of each review was judged on a scale from 1 to 5 by an editor who was blinded to the identity of the reviewer. Reviewer characteristics were taken from the curricula vitae. 86 of the 201 reviewers (43%) produced good reviews (a grade of 4 or 5). Using logistic regression, the authors found that when a reviewer was less than 40 years old, from a top academic institution, well known to the editor choosing the reviewer, and blinded to the identity of the manuscript's authors, the probability that he or she would produce a good review was 87%, whereas a reviewer without any of these characteristics had a 7% probability of producing a good review. Other characteristics that were significant only on bivariate analysis included previous clinical research training, additional postgraduate degrees, and more time spent on the review. There was a negative but statistically nonsignificant association between academic rank and review quality: 37% of full professors, 39% of associate professors, and 51% of assistant professors or fellows produced good reviews (p = 0.11). CONCLUSIONS: Good peer reviewers for this journal tended to be young, from strong academic institutions, well known to the editors, and blinded to the identity of the manuscript's authors.

Management of infants at risk for occult bacteremia: a decision analysis.

Because febrile infants with no obvious source of bacterial infection may have bacteremia, and because bacteremia is difficult to diagnose on clinical grounds, we used decision analysis to evaluate whether such infants should be treated with antibiotics, tested further, or sent home. Using a simple decision tree, we found that the decision to give empiric antibiotic treatment is the decision of choice. The difference in quality-adjusted life expectancy between the "best" and "worst" decisions was only 11 days. However, this difference translated to prevention of death or permanent disability in 60 cases per 100,000 febrile children. Further, empiric treatment remained the best management alternative unless the probability of bacteremia was less than 1.4% (less than any published prevalence), or the efficacy of treatment was less than 21%. Our analysis demonstrated that a test with far greater sensitivity than leukocyte count or other tests currently in use is needed to justify testing rather than treating empirically. Further, an enormous patient population would be needed to find a difference of both clinical and statistical significance between treated and untreated patients in a controlled trial. In the absence of such trials, we recommend blood culture and empiric antibiotic treatment of all infants at risk for occult bacteremia.

Hypermedia in medical decision analysis: HyperDecision.

Early in the evolution of medical decision analysis, computers were employed to remove the tedium and insure the accuracy of repetitive calculations, a capacity they still serve today. However, user interfaces could be so complex as to be overwhelming, except for the capable few who designed them or used them often. HyperDecision is a hypercard-based decision analysis program with a simple user interface. A comprehensive tutorial and generic decision tree are integrated so that the fledgling user, whether medical student or seasoned clinician lacking evolved computer and/or decision analysis skills, can reap the benefits of computer support in their clinical practice. In the current political environment surrounding the practice of medicine, having easily accessible tools for both teaching and using medical decision analysis to evaluate and present the rational for medical decisions has taken on a new importance which the medical community must remain abreast of as we move toward the 21st century.

Expert testimony based on decision analysis: a malpractice case report.

OBJECTIVE: Expert testimony in malpractice cases is often subjective and biased. Decision-analytic techniques might provide an objective basis for such testimony. DESIGN: Case report. This article reports the case of a patient with chest pain that resulted in a malpractice suit alleging a delay in diagnosis of coronary artery disease. SETTING: The case occurred in a private practice; the expert witnesses and the decision analysis originated from a university teaching hospital. METHODS: A decision tree and threshold analysis were used to define the thresholds of disease probability at which either testing or treatment should be implemented. The expert testimony of two witnesses that exercise stress testing was the standard of care was compared with the results of the decision analysis. MAIN RESULTS: Decision analysis supported the view that cardiac catheterization would have been the more appropriate test. CONCLUSIONS: Techniques of decision analysis provide a structured and quantitative basis for empirical judgment and may help to minimize current problems with expert testimony.