Development and prognosis of non-Q-wave myocardial infarction in the thrombolytic era

BACKGROUND

Data on non-Q myocardial infarctions (MI) are derived primarily from prethrombolytic era studies. Previous trials demonstrated different development rates and none reported on clinical outcomes.

METHODS

Our goal was to determine the incidence and prognosis of non-Q-wave MI among patients with ST-segment elevation receiving thrombolysis. A retrospective analysis of 5 randomized controlled trials was made. The main outcome measures included rates of (1) transformation of ST-segment elevation to Q- and non-Q-wave MI and (2) inhospital and 1-year mortality and reinfarction among patients who subsequently develop a Q or non-Q MI postthrombolysis as compared to controls.

RESULTS

Non-Q wave development was greater among patients receiving thrombolysis versus placebo/control (3.1% absolute difference, 95% CI 1.2%-5.0%). Among patients receiving thrombolysis, those who developed a non-Q MI experienced significantly lower inhospital and 1-year mortality (absolute differences -3.8% [95% CI -5.2% to -2.4%] and -6.4% [95% CI -9.9% to -3.0%], respectively) and reinfarction (absolute differences -2.9% [95% CI -4.3% to -1.6%] and -3.5% [95% CI -6.1% to -0.9%], respectively) rates, compared with those who evolved a Q MI. Inhospital and 1-year mortality was also significantly lower when compared to placebo/control patients who developed a non-Q MI (absolute differences 4.6% [95% CI -8.2% to -1.1%] and -7.5% [95% CI -12.5% to -2.5%], respectively).

CONCLUSIONS

Patients receiving thrombolysis more often develop a non-Q-wave MI and have a better prognosis than either those who develop a Q MI postthrombolysis or a non-Q MI after standard medical therapy.

Primary prevention drug therapy: can it meet patients' requirements for reduced risk?

The objective was to identify, in primary prevention, patients whose "required risk reduction" (ReqRR) is greater than the "achievable risk reduction" (ARR) that cholesterol-lowering or antihypertensive medication could provide. Individualized estimates of 10-year coronary heart disease or stroke risk were derived for 66 hypercholesterolemic (HC) and 64 hypertensive (HT) patients without symptomatic cardiovascular disease. These estimates were used in trade-off tasks identifying each individual's ReqRR. Then individual ARRs were estimated (in HC patients by assuming total cholesterol/high density lipoprotein ratio reductions to 5.0; in HT patients by assuming systolic blood pressure reductions to 120 mmHg). 12 (18%) HC and 12 (19%) HT subjects would refuse medication regardless of the risk reduction offered. Of the remaining patients, 15/54 (28%; 95% C.I.:16-40%) HC and 19/52 (37%; 95% C.I: 24-51%) HT subjects were "over-requirers," in that their ReqRR/ARR ratio was 1.5. There maybe a notable proportion of patients whose ReqRR is considerably greater than what is achievable, implying that decision aids may help individuals clarify preferences about accepting/refusing medication for the primary prevention of cardiovascular disease.

Biology or bias: practice patterns and long-term outcomes for men and women with acute myocardial infarction

OBJECTIVES

The goal of our study was to examine how age and gender affect the use of coronary angiography and the intensity of cardiac follow-up care within the first year after acute myocardial infarction (AMI). Another objective was to evaluate the association of age, gender and treatment intensity with five-year survival after AMI.

BACKGROUND

Utilization rates of specialized cardiac services inversely correlate with age. Gender-specific practice patterns may also vary with age in a manner similar to known age-gender survival differences after AMI.

METHODS

Using linked population-based administrative data, we examined the association of age and gender with treatment intensity and long-term survival among 25,697 patients hospitalized with AMI in Ontario between April 1, 1992, and December 31, 1993. A Cox proportional hazards model was used to adjust for socioeconomic status, illness severity, attending physician specialty and admitting hospital characteristics.

RESULTS

After adjusting for baseline differences, the relative rates of angiography and follow-up specialist care for women relative to men, respectively, fell 17.5% (95% confidence interval [CI], 13.6 to 21.3, p < 0.001) and 10.2% (95% CI, 7.1 to 13.2, p < 0.001) for every 10-year increase in age. Conversely, long-term AMI survival rates in women relative to men improved with increasing age, such that the relative survival in women rose 14.2% (95% CI, 10.1 to 17.5, p < 0.001) for every 10-year age increase.

CONCLUSIONS

Gender differences in the intensity of invasive testing and follow-up care are strongly age-specific. While care becomes progressively less aggressive among older women relative to men, survival advantages track in the opposite direction, with older women clearly favored. These findings suggest that biology is likely to remain the main determinant of long-term survival after AMI for women.

Accelerated publication versus usual publication in 2 leading medical journals

BACKGROUND

A number of medical journals have developed policies for accelerated publication of articles judged by the authors, the editors or the peer reviewers to be of special importance. However, the validity of these judgements is unknown. We therefore compared the importance of articles published on a "fast track" with those published in the usual way.

METHODS

We identified 12 "case" articles--6 articles from the New England Journal of Medicine that were prereleased on the journal's Web site before publication in print and 6 "fast-tracked" articles from The Lancet. We then identified 12 "control" articles matched to the case articles according to journal, disease or procedure of focus, theme area and year of publication. Forty-two general internists rated the articles, using 10-point scales, on dimensions addressing the articles' importance, ease of applicability and impact on health outcomes.

RESULTS

For each dimension, the mean score for the case articles was significantly higher than the mean score for the control articles: importance to clinical practice 7.6 v. 7.1 respectively (p = 0.001), importance from a public health perspective 6.5 v. 6.0 (p < 0.001), contribution to advancement of medical knowledge 6.2 v. 5.8 (p < 0.001), ease of applicability in practice 7.0 v. 6.5 (p < 0.001), potential impact on health outcomes 6.5 v. 5.9 (p < 0.001). Despite these general findings, in 5 of the 12 matched pairs of articles the control article had a higher mean score than the case article across all the dimensions.

INTERPRETATION

The accelerated publication practices of 2 leading medical journals targeted articles that, on average, had slightly higher importance scores than similar articles published in the usual way. However, our finding of higher importance scores for control articles in 5 of the 12 matched pairs shows that current journal practices for selecting articles for expedited publication are inconsistent.

Using disease risk estimates to guide risk factor interventions: field test of a patient workbook for self-assessing coronary risk

OBJECTIVE

To assess the feasibility and acceptability of a patient workbook for self-assessing coronary risk.

DESIGN

Pilot study, with post-study physician and patient interviews.

SETTING AND SUBJECTS

Twenty southern Ontario family doctors and 40 patients for whom they would have used the workbook under normal practice conditions.

INTERVENTIONS

The study involved convening two sequential groups of family physicians: the first (n=10) attended focus group meetings to help develop the workbook (using algorithms from the Framingham Heart Study); the second (n=20) used the workbook in practice with 40 patients. Follow-up interviews were by interviewer-administered questionnaire.

MAIN OUTCOMES MEASURES

Physicians' and patients' opinions of the workbook's format, content, helpfulness, feasibility, and potential for broad application, as well as patients' perceived 10-year risk of a coronary event measured before and after using the workbook.

RESULTS

It took an average of 18 minutes of physician time to use the workbook: roughly 7 minutes to introduce it to patients, and about 11 minutes to discuss the results. Assessments of the workbook were generally favourable. Most patients were able to complete it on their own (78%), felt they had learned something (80%) and were willing to recommend it to someone else (98%). Similarly, 19 of 20 physicians found it helpful and would use it in practice with an average of 18% of their patients (range: 1-80%). The workbook helped to correct misperceptions patients had about their personal risk of a coronary event over the next 10 years (pre-workbook (mean (SD) %): 35.2 (16.9) vs. post-workbook: 17.3 (13.5), P < 0.0001; estimate according to algorithm: 10.6 (7.6)).

CONCLUSIONS

Given a simple tool, patients can and will assess their own risk of CHD. Such tools could help inform otherwise healthy individuals that their risk is increased, allowing them to make more informed decisions about their behaviours and treatment.

Factoring socioeconomic status into cardiac performance profiling for hospitals: does it matter?

BACKGROUND

Critics of "scorecard medicine" often highlight the incompleteness of risk-adjustment methods used when accounting for baseline patient differences. Although socioeconomic status is a highly important determinant of adverse outcome for patients admitted to the hospital with acute myocardial infarction, it has not been used in most risk-adjustment models for cardiovascular report cards.

OBJECTIVES

To determine the incremental impact of socioeconomic status adjustments on age, sex, and illness severity for hospital-specific 30-day mortality rates after acute myocardial infarction.

METHODS

The authors compared the absolute and relative hospital-specific 30-day acute myocardial infarction mortality rates in 169 hospitals throughout Ontario between April 1, 1994 and March 31, 1997. Patient socioeconomic status was characterized by median neighborhood income using postal codes and 1996 Canadian census data. They examined two risk-adjustment models: the first adjusted for age, sex, and illness severity (standard), whereas the second adjusted for age, sex, illness severity, and median neighborhood income level (socioeconomic status).

RESULTS

There was an extremely strong correlation between 'standard' and 'socioeconomic status' risk-adjusted mortality rates (r = 0.99). Absolute differences in 30-day risk-adjusted mortality rates between the socioeconomic status and standard risk-adjustment models were small (median, 0.1%; 25th-75th percentile, 0.1-0.2). The agreement in the quintile rankings of hospitals between the socioeconomic status and standard risk-adjustment models was high (weighted kappa = 0.93).

CONCLUSION

Despite its importance as a determinant of patient outcomes, the effect of socioeconomic status on hospital-specific mortality rates over and above standard risk-adjustment methods for acute myocardial infarction hospital profiling in Ontario was negligible.

Parkinsonism in Ontario: increased mortality compared with controls in a large cohort study

BACKGROUND

PD was associated with increased mortality before levodopa therapy became available. There have been conflicting reports of PD mortality in the modern era.

OBJECTIVE

To assess current mortality rates in a large unselected population receiving treatment for parkinsonism (PKM) followed for up to 6 years.

METHODS

Cases were identified using linked administrative databases, including physician service and prescription drug claims, generated in Ontario's universal health insurance system. Control subjects were identified from the provincial registry of citizens and age and sex matched to cases. Comparative mortality was evaluated over the 6-year period of the study (1993/94 to 1998/99). The sensitivity of the findings was tested with differing case definitions.

RESULTS

In 1993, 15,304 patients with PKM were identified and were age and sex matched to 30,608 control subjects (1:2 ratio). Over the study period, 50.8% (7,779) of the cases with PKM died compared with 29.1% (8,899) of the control subjects. The cases with PKM had an overall mortality odds ratio of 2.5 (95% CI: 2.4, 2.6) compared with the control group. Results were consistent whether cases were defined by physician diagnosis, use of anti-PD drugs, or both criteria.

CONCLUSION

Despite modern drug therapy, PKM continues to confer a sharply increased mortality on unselected patients followed for several years.

Long-term MI outcomes at hospitals with or without on-site revascularization

CONTEXT

Many studies have found that patients with acute myocardial infarction (AMI) who are admitted to hospitals with on-site revascularization facilities have higher rates of invasive cardiac procedures and better outcomes than patients in hospitals without such facilities. Whether such differences are due to invasive procedure rates alone or to other patient, physician, and hospital characteristics is unknown.

OBJECTIVE

To determine whether invasive procedural rate variations alone account for outcome differences in patients with AMI admitted to hospitals with or without on-site revascularization facilities.

DESIGN

Retrospective, observational cohort study using linked population-based administrative data from a universal health insurance system.

SETTING

One hundred ninety acute care hospitals in Ontario, 9 of which offered invasive procedures.

PATIENTS

A total of 25 697 patients hospitalized with AMI between April 1, 1992, and December 31, 1993, of whom 2832 (11%) were in invasive hospitals.

MAIN OUTCOME MEASURES

Mortality, recurrent cardiac hospitalizations, and emergency department visits in the 5 years following the index admission, adjusted for patient age, sex, socioeconomic status, illness severity, and index revascularization procedures; attending physician specialty; and hospital volume, teaching status, and geographical proximity to invasive-procedure centers and compared by hospital type.

RESULTS

Patients admitted to invasive-procedure hospitals were much more likely to undergo revascularization (11.4% vs 3.2% at other hospitals; P<.001). However, many other clinical and process-related factors differed between the 2 groups. Although mortality rates were similar between the 2 institution types, the nonfatal composite 5-year event rate (ie, recurrent cardiac hospitalization and emergency department visits) was lower for patients initially admitted to invasive-procedure hospitals (71.3% vs 80.4%; unadjusted odds ratio [OR], 0.65; 95% confidence interval [CI], 0.52-0.82; P<.001). This advantage persisted after adjustment for sociodemographic and clinical factors and procedure utilization (adjusted OR, 0.68; 95% CI, 0.53-0.89; P<.001). However, the nonfatal outcome advantages of invasive-procedure hospitals were explained by their teaching status (adjusted OR, 0.98; 95% CI, 0.73-1.30; P =.87).

CONCLUSIONS

In this sample of patients admitted with AMI, the differing outcomes of apparently similar patients treated in 2 different practice settings were explained by multiple competing factors. Researchers conducting observational studies should be cautious about attributing patient outcome differences to any single factor.

Major trauma in elderly adults receiving lipid-lowering medications

BACKGROUND

Some clinical trials, laboratory experiments, and in vitro studies suggest that lipid-lowering medications predispose a person to traumatic injury.

METHODS

We used population-based administrative database analysis to study adults age 65 years or more over a 5-year interval (n = 1,348,259).

RESULTS

About 12% of the cohort received a prescription for a lipid-lowering medication and about 88% did not. The two groups had similar distributions of age, gender, and income. Overall, 2,557 (0.2%) were hospitalized for major trauma. Those who received a lipid-lowering medication were 39% less likely to sustain a major trauma than those who did not receive such medication (95% confidence interval, 29 to 47). Similar results were observed after adjustment for age, gender, and income; cardiac and neurologic medications; and lethality. No other cardiac or neurologic medication was associated with an apparent safety advantage.

CONCLUSION

Lipid-lowering medications do not lead to a clinically important increase in the absolute risk of major trauma for elderly patients in the community.

A comparison of a Bayesian vs. a frequentist method for profiling hospital performance

The objective of this study was to compare the classification of hospitals as outcomes outliers using a commonly implemented frequentist statistical approach vs. an implementation of Bayesian hierarchical statistical models, using 30-day hospital-level mortality rates for a cohort of acute myocardial infarction patients as a test case. For the frequentist approach, a logistic regression model was constructed to predict mortality. For each hospital, a risk-adj usted mortality rate was computed. Those hospitals whose 95% confidence interval, around the risk-adjusted mortality rate, excludes the mean mortality rate were classified as outliers. With the Bayesian hierarchical models, three factors could vary: the profile of the typical patient (low, medium or high risk), the extent to which the mortality rate for the typical patient departed from average, and the probability that the mortality rate was indeed different by the specified amount. The agreement between the two methods was compared for different patient profiles, threshold differences from the average and probabilities. Only marginal agreement was shown between the Bayesian and frequentist approaches. In only five of the 27 comparisons was the kappa statistic at least 0.40. The remaining 22 comparisons demonstrated only marginal agreement between the two methods. Within the Bayesian framework, hospital classification clearly depended on patient profile, threshold and probability of exceeding the threshold. These inconsistencies raise questions about the validity of current methods for classifying hospital performance, and suggest a need for urgent research into which methods are most meaningful to clinicians, managers and the general public.

Vitamin B12 injections versus oral supplements. How much money could be saved by switching from injections to pills?

OBJECTIVE

To estimate savings, using a third-party payer perspective, if all elderly patients currently receiving vitamin B12 (cobalamin) injections were switched to high-dose oral therapy.

DESIGN

We modeled high-dose oral B12 supplement costs to include drugs, pharmacists' fees, and one-time conversion costs consisting of two physician visits and laboratory monitoring. The number of vitamin-injection visits avoided by switching to oral therapy was predicted using a multivariate model that considered covariates for overall patient illness.

SETTING

Ontario family physicians' and internists' practices.

PARTICIPANTS

Population-based administrative databases for Ontario were used to identify all people between 65 and 100 years who received parenteral vitamin B12 during 1995 and 1996.

MAIN OUTCOME MEASURES

The cost of parenteral vitamin B12 for each patient, including drugs, injections, pharmacists' fees, and injection-associated physician visits, was measured directly from the databases.

RESULTS

The annual cost of parenteral vitamin B12 therapy averaged $145.88 per person and totaled a maximum $25 million over 5 years. Converting all patients to high-dose oral B12 and treating them for 5 years would cost $7.4 million. Depending on how many vitamin-injection visits are avoided by switching to oral therapy, between $2.9 million and $17.6 million would be saved. Switching to oral B12 administration saved costs as long as 16.3% of injection-associated visits were avoided.

CONCLUSION

Switching all patients from B12 injections to oral cobalamin therapy could result in substantial savings.

Prognostic significance of diabetes as a predictor of survival after cardiac catheterization. APPROACH Investigators. Alberta Provincial Program for Outcome Assessment in Coronary Heart Disease

PURPOSE

Diabetes is a recognized risk factor for the development of cardiac disease, but its importance as a prognostic factor among patients with known cardiovascular disease is less clear. We evaluated survival in patients with and without diabetes who underwent cardiac catheterization for presumed coronary artery disease.

SUBJECTS AND METHODS

We analyzed data from a prospective cohort study that captures detailed clinical information and longitudinal outcomes for all patients who undergo cardiac catheterization in Alberta, Canada. We studied 11,468 patients, 1959 (17%) of whom had diabetes. Logistic regression was used to model predictors of 1-year mortality, and proportional hazards analysis was used to model predictors of survival up to 3 years after cardiac catheterization.

RESULTS

One-year mortality was 7.6% for patients with diabetes versus 4.1% for those without diabetes (odds ratio = 1.9, 95% confidence interval [CI]: 1.6 to 2.3). After adjusting for other characteristics of the patients, including comorbid conditions, previous cardiac history, coronary anatomy, and renal function, the odds ratio for 1-year mortality was 1.1 (95% CI: 0.8 to 1.3). Similarly, the adjusted hazard ratio for longer term mortality was 1. 2 (95% CI: 1.0 to 1.4, mean follow-up of 702 days).

CONCLUSIONS

These results suggest that there is little or no independent association between diabetes and mortality for up to 3 years after cardiac catheterization. Estimates of short- to intermediate-term prognosis for diabetic patients with coronary artery disease should be based on the presence of other prognostic factors associated with diabetes.

Users' Guides to the Medical Literature: XXV. Evidence-based medicine: principles for applying the Users' Guides to patient care. Evidence-Based Medicine Working Group

This series provides clinicians with strategies and tools to interpret and integrate evidence from published research in their care of patients. The 2 key principles for applying all the articles in this series to patient care relate to the value-laden nature of clinical decisions and to the hierarchy of evidence postulated by evidence-based medicine. Clinicians need to be able to distinguish high from low quality in primary studies, systematic reviews, practice guidelines, and other integrative research focused on management recommendations. An evidence-based practitioner must also understand the patient's circumstances or predicament; identify knowledge gaps and frame questions to fill those gaps; conduct an efficient literature search; critically appraise the research evidence; and apply that evidence to patient care. However, treatment judgments often reflect clinician or societal values concerning whether intervention benefits are worth the cost. Many unanswered questions concerning how to elicit preferences and how to incorporate them in clinical encounters constitute an enormously challenging frontier for evidence-based medicine. Time limitation remains the biggest obstacle to evidence-based practice but clinicians should seek evidence from as high in the appropriate hierarchy of evidence as possible, and every clinical decision should be geared toward the particular circumstances of the patient.

Rate of heart failure and 1-year survival for older people receiving low-dose beta-blocker therapy after myocardial infarction

BACKGROUND

Many older people do not receive beta-blocker therapy after myocardial infarction or receive doses lower than those tested in trials, perhaps because physicians fear that beta-blockers may precipitate heart failure. We examined the relation between use of beta-blockers, the dose used, and hospital admission for heart failure and 1-year survival in a cohort of all older patients surviving myocardial infarction in Ontario, Canada.

METHODS

We collected data on a cohort of 13,623 patients aged 66 years or older who were discharged from hospital after a myocardial infarction and who did not receive beta-blocker therapy or received low, standard, or high doses. We used Cox's proportional-hazards models to study the association of dose with admission for heart failure and survival with adjustment for factors including age, sex, and comorbidity.

FINDINGS

Among 8232 patients with no previous history of heart failure, dispensing of beta-blocker therapy was associated with a 43% reduction in subsequent admission for heart failure (adjusted risk ratio 0.57 [95% CI 0.48-0.69]) compared with patients not dispensed this therapy. Among the 4681 patients prescribed beta-blockers, the risk of admission was greater in the high-dose than in the low-dose group (1.53 [1.01-2.31]). Among all 13,623 patients in the cohort, 2326 (17.1%) died by 1 year. Compared with those not dispensed beta-blocker therapy, the adjusted risk ratio for mortality was lower for all three doses (low 0.40 [0.34-0.47], standard 0.36 [0.31-0.42], high 0.43 [0.33-0.56]).

INTERPRETATION

Compared with high-dose beta-blocker therapy, low-dose treatment is associated with a lower rate of hospital admission for heart failure and has a similar 1-year survival benefit. Our findings support the need for a randomised controlled trial comparing doses of beta-blocker therapy in elderly patients.

Users' guides to the medical literature: XXIV. How to use an article on the clinical manifestations of disease. Evidence-Based Medicine Working Group

Clinicians rely on knowledge about the clinical manifestations of disease to make clinical diagnoses. Before using research on the frequency of clinical features found in patients with a disease, clinicians should appraise the evidence for its validity, results, and applicability. For validity, 4 issues are important-how the diagnoses were verified, how the study sample relates to all patients with the disease, how the clinical findings were sought, and how the clinical findings were characterized. Ideally, investigators will verify the presence of disease in study patients using credible criteria that are independent of the clinical manifestations under study. Also, ideally the study patients will represent the full spectrum of the disease, undergo a thorough and consistent search for clinical findings, and these findings will be well characterized in nature and timing. The main results of these studies are expressed as the number and percentages of patients with each manifestation. Confidence intervals can describe the precision of these frequencies. Most clinical findings occur with only intermediate frequency, and since these frequencies are equivalent to diagnostic sensitivities, this means that the absence of a single finding is rarely powerful enough to exclude the disease. Before acting on the evidence, clinicians should consider whether it applies to their own patients and whether it has been superseded by new developments. Detailed knowledge of the clinical manifestations of disease should increase clinicians' ability to raise diagnostic hypotheses, select differential diagnoses, and verify final diagnoses. JAMA. 2000;284:869-875

Users' guides to the medical literature: XXII: how to use articles about clinical decision rules. Evidence-Based Medicine Working Group

Clinical experience provides clinicians with an intuitive sense of which findings on history, physical examination, and investigation are critical in making an accurate diagnosis, or an accurate assessment of a patient's fate. A clinical decision rule (CDR) is a clinical tool that quantifies the individual contributions that various components of the history, physical examination, and basic laboratory results make toward the diagnosis, prognosis, or likely response to treatment in a patient. Clinical decision rules attempt to formally test, simplify, and increase the accuracy of clinicians' diagnostic and prognostic assessments. Existing CDRs guide clinicians, establish pretest probability, provide screening tests for common problems, and estimate risk. Three steps are involved in the development and testing of a CDR: creation of the rule, testing or validating the rule, and assessing the impact of the rule on clinical behavior. Clinicians evaluating CDRs for possible clinical use should assess the following components: the method of derivation; the validation of the CDR to ensure that its repeated use leads to the same results; and its predictive power. We consider CDRs that have been validated in a new clinical setting to be level 1 CDRs and most appropriate for implementation. Level 1 CDRs have the potential to inform clinical judgment, to change clinical behavior, and to reduce unnecessary costs, while maintaining quality of care and patient satisfaction. JAMA. 2000;284:79-84

Predictive accuracy study: comparing a statistical model to clinicians' estimates of outcomes after coronary bypass surgery

BACKGROUND

The purpose of this study was to compare clinicians' prior probability estimates of operative mortality (OM) and prolonged intensive care unit stay (ICU) length of stay greater than 48 hours after coronary artery bypass graft surgery (CABG) with estimates derived from statistical models alone.

METHODS

Nine clinicians estimated the predicted probability of OM and ICU stay greater than 48 hours from an abstract of information for each of 100 patients selected from the 1996 to 1997 database of 1,904 patients who underwent isolated CABG. Logistic regression models were used to calculate the predicted probability of OM and ICU stay greater than 48 hours for each patient. The study sample was split into two parts; clinicians were randomly given access to a predictive rule to guide their judgements for one part of the study.

RESULTS

Clinicians' estimates were similar with or without access to the rule, and both parts of the study were therefore pooled. Clinicians significantly overestimated the probability of OM (model 6.3% +/- 1%, clinicians 7.6% +/- 3%, p = 0.0001) and ICU stay greater than 48 hours (model 25% +/- 2%, clinicians 28% +/- 1%, p = 0.0012). Clinicians' estimates of OM were not significantly higher than the model's for nonsurvivors (0.8% +/- 0.7%, p = 0.2), but were significantly higher for survivors (1.4% +/- 0.3%, p = 0.039).

CONCLUSIONS

Clinicians trusted their own empiric estimates rather than a predictive rule and overestimated the probability of OM and ICU stay greater than 48 hours.