Robert M. Centor

The diagnosis of strep throat in adults in the emergency room.

Adult patients who presented to an urban emergency room complaining of a sore throat had cultures and clinical information recorded. Models were constructed, using logistic regression analysis, of both a positive culture for Group A beta streptococcus and a positive guess by a resident. The model of a positive culture consisted of four variables--tonsillar exudates, swollen tender anterior cervical nodes, lack of a cough, and history of fever. Patients with all 4 variables had a 56% probability of a positive culture; 3 variables, 32%; 2 variables, 15%; 1 variable, 6.5%; and 0 variables, 2.5%. The model of a positive guess by a resident demonstrated an over-reliance on physical exam and an underuse of history. The model of a positive culture allows stratification of patients to assist clinicians in the management strategies.

Screening for Alcohol Abuse Using CAGE Scores and Likelihood Ratios

OBJECTIVE To assess the performance of the CAGE (acronym referring to four questions, see below) questionnaire in discriminating between medicine outpatients with and without an alcohol abuse or dependence disorder. DESIGN A cross-sectional design of a sample of consecutive patients who received both the alcohol module of the diagnostic interview schedule and the CAGE (Cut down, Annoyed, Guilty, Eye-opener) screening questionnaire. SETTING The outpatient medical practice of an urban university teaching hospital. PATIENTS All patients 18 years or older who signed a consent form approved by the universitys institutional review board. MEASUREMENT Calculation of the sensitivity, specificity, receiver operating characteristic (ROC) curve, and likelihood ratio for CAGE scores of 0 to 4. RESULTS Thirty-six percent of the sample group met criteria for a history of alcohol abuse or dependence. A CAGE score of 2 or more was associated with a sensitivity and specificity of 74% and 91%. The calculated area under the ROC curve was 0.89, whereas the likelihood ratios for CAGE scores of 0 to 4 were 0.14, 1.5, 4.5, 13, and 100, respectively. These ratios were associated with posterior probabilities for an abuse or dependence disorder of 7%, 46%, 72%, 88%, and 98%, respectively. CONCLUSION Clinicians can improve their ability to estimate a patients risk for an alcohol abuse or dependence disorder using likelihood ratios for CAGE scores.

Reassessment of clinical practice guidelines: go gently into that good night.

IN 1990, THE INSTITUTE OF MEDICINE PROPOSED GUIDEline development to reduce inappropriate health care variation by assisting patient and practitioner decisions. Unfortunately, too many current guidelines have become marketing and opinion-based pieces, delivering directive rather than assistive statements. Current use of the term guideline has strayed far from the original intent of the Institute of Medicine. Most current articles called “guidelines” are actually expert consensus reports. It is not surprising, then, that the article by Tricoci et al in this issue of JAMA demonstrates that revisions of the American College of Cardiology (ACC)/American Heart Association (AHA) guidelines have shifted to more class II recommendations (conflicting evidence and/or divergence of opinion about the usefulness/efficacy of a procedure or treatment) and that 48% of the time, these recommendations are based on the lowest level of evidence (level C: expert opinion, case studies, or standards of care). This trend is especially disconcerting given the quantity of cardiovascular scientific literature published during the last decade. The overreliance on expert opinion in guidelines is problematic. All guideline committees begin with implicit biases and values, which affects the recommendations they make. However, bias may occur subconsciously and, therefore, go unrecognized. Converting data into recommendations requires subjective judgments; the value structure of the panel members molds those judgments. Guideline consumers could adjust for these biases if guideline panels made their values and goals explicit, but usually they remain opaque. The most widely recognized bias is financial. Guidelines often have become marketing tools for device and pharmaceutical manufacturers. While the ACC and AHA receive no industry funding for guideline development, they do receive industry support to disseminate guideline products such as pocket guides. Financial ties between guideline panel members and industry are common. “Experts” on guideline panels are more likely to receive industry funding for research, consulting fees, and speakers’ honoraria. In 1 study of 44 guidelines, 87% of the guideline authors had some form of industry tie. Other biases are also important. The specialty composition of a guideline panel likely influences guideline development. Specialty societies can use guidelines to enlarge that specialty’s area of expertise in a competitive medical marketplace. Federal guideline committees may focus on limiting costs; committees influenced by industry are more likely to shape recommendations to accord with industry needs. Guidelines have other limitations. Guidelines are often too narrowly focused on single diseases and are not patient focused. Patients seldom have single diseases, and few if any guidelines help clinicians in managing complexity. Paradoxically, guidelines are also often too comprehensive, covering every possible intervention that could be appropriate for a patient with that single disease. Tricoci et al found that in ACC/AHA guidelines with at least 1 revision, the number of recommendations increased 48% from the first guideline to the most recent version. If there is a main message in such guidelines, it is likely to be lost in the minutiae. Guidelines are not patient-specific enough to be useful and rarely allow for individualization of care. Most guidelines have a one-size-fits-all mentality and do not build flexibility or contextualization into the recommendations. There are simply too many guidelines, often on the same topic. For instance, clinicians really do not need 10 different adult pharyngitis guidelines. Moreover, guidelines are often out of date. The evidence base used to create guidelines changes quickly. Most guidelines become outdated after 5 years, and most guideline developers lack formal procedures for updating their guidelines. The ACC/AHA guidelines are periodically updated, with updates taking a mean of 4.6 to 8.2 years until publication. As a result, many clinicians do not use guidelines. An even greater concern, however, is that some of these consensus statements are being turned into performance measures and other tools to critique the quality of physician care. This potential problem could be minimized if performance measures were derived from high-quality guidelines based on the highest level of evidence and applied to patients with a

Screening for Drinking Disorders in the Elderly Using the CAGE Questionnaire

To assess the performance of the CAGE questionnaire in identifying elderly medicine outpatients with drinking problems.

Physician internet medical information seeking and on‐line continuing education use patterns

Introduction: Although physician Internet use patterns have been studied, little attention has been paid to how current physician learning and change theories relate to physician Internet information seeking and on‐line learning behaviors. The purpose of this study was to examine physician medical information–seeking behaviors and their relevance to continuing education (CE) providers who design and develop on‐line CE activities. Methods: A survey concerning Internet use and learning was administered by facsimile transmission to a random sample of 2,200 U.S. office‐based physicians of all specialties. Results: Nearly all physicians have access to the Internet, know how to use it, and access it for medical information; the Internets professional importance to physicians currently is in the area of professional development and information seeking to provide better care rather than for patient‐physician communication. A particular patient problem was the most common reason for seeking information. The credibility of the source, quick and 24‐hour access to information, and ease of searching were most important to physicians. Barriers to use included too much information to scan and too little specific information to respond to a defined question. Discussion: The importance of the Internet to physician professional development is growing rapidly. Access to on‐line continuing medical education must be immediate, relevant, credible, and easy to use. A sense of high utility demands content that is focused and well indexed. The roles of the CE provider must be reshaped to include helping physicians seek and construct the kind of knowledge they need to improve patient care.

Choice of long-term strategy for the management of patients with severe esophagitis : A cost-utility analysis

BACKGROUND & AIMS Omeprazole has shown remarkable efficacy and safety in the treatment of patients with gastroesophageal reflux disease (GERD); similarly, laparoscopic techniques have allowed less morbidity in patients undergoing fundoplication procedures. Concerns about the long-term cost and safety of both strategies have prompted a debate of their role in long-term management of patients with severe erosive esophagitis. METHODS A cost-utility analysis was performed to compare two strategies: laparoscopic Nissen fundoplication (LNF) vs. omeprazole. A two-stage Markov model was used to obtain cost and efficacy estimates; all estimates were discounted at 3% per year. The time horizon was 5 years. Sensitivity analyses were performed on all relevant variables. RESULTS Both strategies were similarly effective (4.33 quality-adjusted life years per patient), with omeprazole less expensive than LNF (

Nurse staffing and mortality for Medicare patients with acute myocardial infarction

6053 vs.

An Evaluation of Methods for Estimating the Area Under the Receiver Operating Characteristic (ROC) Curve

9482 per patient). At 10 years, LNF and omeprazole costs were similar. Efficacy estimates were extremely sensitive to changes in quality of life associated with postoperative symptoms and long-term use of medication. CONCLUSIONS Medical therapy is the preferred treatment strategy for most patients with severe erosive esophagitis. Individuals with a long life expectancy are good candidates for LNF if postoperative morbidity is low and GERD symptoms remain abated for many years.

Racial differences in the medical treatment of elderly medicare patients with acute myocardial infarction

ContextRecent hospital reductions in registered nurses (RNs) for hospital care raise concerns about patient outcomes. ObjectiveAssess the association of nurse staffing with in-hospital mortality for patients with acute myocardial infarction (AMI). Design, Setting, and Patients.Medical record review data from the 1994–1995 Cooperative Cardiovascular Project were linked with American Hospital Association data for 118,940 fee-for-service Medicare patients hospitalized with AMI. Staffing levels were represented as nurse to patient ratios categorized into quartiles for RNs and for licensed practical nurses (LPNs). Main Outcome Measures.In-hospital mortality. ResultsFrom highest to lowest quartile of RN staffing, in-hospital mortality was 17.8%, 17.4%, 18.5%, and 20.1%, respectively (P < 0.001 for trend). However, from highest to lowest quartile of LPN staffing, mortality was 20.1%, 18.7%, 17.9%, and 17.2%, respectively P < 0.001). After adjustment for patient demographic and clinical characteristics, treatment, and for hospital volume, technology index, and teaching and urban status, patients treated in environments with higher RN staffing were less likely to die in-hospital; odds ratios (95% confidence intervals) of quartiles 4, 3, and 2 versus quartile 1 were 0.91 (0.86–0.97), 0.94 (0.88–1.00), and 0.96 (0.90–1.02), respectively. Conversely, after adjustment, patients treated in environments with higher LPN staffing were more likely to die in-hospital; odds ratios (95% confidence intervals) of quartiles 4, 3, and 2 versus quartile 1 were 1.07 (1.00–1.15), 1.02 (0.96–1.09), and 1.00 (0.94–1.07), respectively. ConclusionsEven after extensive adjustment, higher RN staffing levels were associated with lower mortality. Our findings suggest an important effect of nurse staffing on in-hospital mortality.

Expand the Pharyngitis Paradigm for Adolescents and Young Adults

The area under the receiver operating characteristic (ROC) curve serves as one means for evaluating the performance of diagnostic and predictive test systems. The most commonly used method for estimating the area under an ROC curve utilizes the maximum-likelihood-estimation technique, and a nonparametric method to calculate the area under an ROC curve was recently described. We compared the performance of these two methods. The results for the area under the ROC curve and the standard error of the estimate as calculated by each of the two methods exhibited high correlation. Generally, the nonparametric method yields lower area estimates than the maximum-likelihood-estimation technique. However, these differences generally were small, particularly with ROC curves derived from five or more cutoff points. Consistent results of hypothesis testing of the significance of differences between two ROC curves will be similar, regardless of which method is used, as long as one uses the same estimation technique on the two curves and as long as the two ROC curves being compared are of similar shape.