Medical decision making : an international journal of the Society for Medical Decision Making
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X-rays taken for ankle trauma contribute significantly to the cost of health care in this country. In an attempt to find clinical correlates of ankle fracture 36 detailed historical and physical examination variables were collected from 587 consecutive patients with ankle trauma, and ankle x-rays were taken of all patients. The association of each variable with the final diagnosis of fracture, rupture, or sprain was tested; 21 variables were significant predictors of fracture (vs. sprain and rupture) and 15 were not significantly associated with final diagnosis. ⋯ This compares favorably with a recently published rule that did not assess sensitivity. A simulated prospective evaluation suggests that these results are stable, but that up to 10% of the fractures could be missed on the first visit. Although current practice is not well documented, it appears that use of this rule could yield substantial cost savings.
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Twenty-five years of appellate court decisions about informed consent in three influential states were examined to address four issues: the criteria used to define adequate informed consent; trends in court decisions; parallels between court decision making and decision analysis; the contribution of decision analytic concepts to defining "reasonable" medical informed consent. Court standards have evolved in three phases: the "medical community" standard before 1972, the "reasonable person" standard since 1972, and recent inroads toward developing an "individual preference" standard. ⋯ Jurists and physicians should consider whether the legal system should adopt a decision analytic perspective in the doctrine of informed consent. Researchers should address issues raised by use of decision analysis for communication between the physician and the patient.
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In a multivariate logistic regression analysis of data from 508 patients, only two clinical factors, age and typicality of pain, were independently significant predictors of left main coronary artery disease. The resulting multivariate equation was prospectively applied to another 370 patients to derive pre-exercise-test (ETT) probabilities of left main coronary artery disease, and these pre-ETT probabilities were combined with literature-derived likelihood ratios for various ETT findings to derive post-ETT probabilities. This model, which can be displayed in simple graphic form, accurately predicted the probability of left main coronary artery disease when prospectively evaluated in this independent validation set of patients. ⋯ While 48% of patients had mid-range (5-15%) probabilities of left main coronary artery disease before the ETT, only 24% fell into this range of probabilities after the ETT (p less than 0.0001), as ETT results moved patients into higher and lower probability ranges. Thus, probability of left main coronary artery disease can be calculated from clinical and ETT data with this model. These estimated pre- and post-ETT probabilities of left main coronary artery disease may aid in the selection of patients for noninvasive testing or for cardiac catheterization.
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Comparative Study
Diagnostic workup bias in the evaluation of a test. Serum ferritin and hereditary hemochromatosis.
Two studies report markedly divergent results about the usefulness of serum ferritin in diagnosing iron overload in relatives of patients with hereditary hemochromatosis. One study found the sensitivity of elevated serum ferritin to be 0%; another study found a sensitivity of 100%. ⋯ In the study reporting a sensitivity of 100%, relatives with normal serum tests may have been excluded from consideration for liver biopsy, thus preventing detection of iron overload. The controversy may provide an empirical illustration of diagnostic workup bias.
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Decision-analytic techniques were used to evaluate the choice between an aortocoronary bypass operation and medical management in a set of hypothetical patients with coronary artery disease. The decision framework incorporates variables believed to have an important bearing on the choice of treatment. Probability estimates were obtained from two cardiologists and one cardiac surgeon. ⋯ In five patients, the physicians' clinical judgments favored medical treatment, whereas their decision-analysis-derived estimates of survival favored operation. Possible explanations for these discrepancies are discussed. A simplified cost-effectiveness analysis for patients in whom surgery was the optimal treatment indicated costs ranging from $1,500 to $250,000 per year of life gained and from $1,500 to $32,000 per quality-adjusted year of life gained.