Neal V. Dawson

Systematic errors in medical decision making: judgment limitations.

Much of medical practice involves the exercise of such basic cognitive tasks as estimating probabilities and synthesizing information. Scientists studying cognitive processes have identified impediments to accurate performance on these tasks. Together the impediments foster “cognitive bias.” Five factors that can detract from accurate probability estimation and three that impair accurate information synthesis are discussed. Examples of all eight factors are illustrated by reference to published articles. The authors suggest ways to minimize the negative influences of these factors.

Does Drug Therapy Slow Radiographic Deterioration in Rheumatoid Arthritis

Many clinicians believe that slow-acting therapeutic agents, such as fold, penicillamine, the antimalarials, and cytotoxic drugs, can retard joint destruction in rheumatoid arthritis. We reviewed 60 published studies employing these drugs to evaluate critically the evidence that drug therapy can slow the radiographic progression of disease. Seventeen studies were found that included radiographic assessment of both treated and control groups; they were analyzed using methodologic criteria known to be important in affecting the results of drug trials. In addition to numerous qualitative methodologic deficiencies, many studies showed inadequacies in sample size and duration of treatment, and the drug dosage used varied from one study to another. We found evidence suggesting that both gold and cyclophosphamide can retard radiographic progression of joint destruction. At present, there are too few technically adequate studies to permit even provisional conclusions concerning other agents.

Preferences for cardiopulmonary resuscitation - Physician-patient agreement and hospital resource use

OBJECTIVE: To describe the association between hospital resource utilization and physicians’ knowledge of patient preferences for cardiopulmonary resuscitation (CPR) among seriously ill hospitalized adult patients.DESIGN: Prospective cohort study.SETTING: Five U.S. academic medical centers, 1989–1991.PATIENTS: A sample of 2,636 patients with self- or surrogate interviews and matching physician interviews describing patient preferences for CPR, from a cohort of 4,301 patients with life-threatening illnesses enrolled in the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments (SUPPORT).MEASURES: Patient, surrogate, and physician reports of preferences for resuscitation, and resource use derived from the Therapeutic Intensity Scoring System and hospital length of stay, converted into 1990 dollars.RESULTS: Nearly one-third of the patients preferred to forge resuscitation. Of the 2,636 paired physician—patient answers, nearly one-third did not agree about preferences for resuscitation. The physicians’ views of the patients’ preferences and those preferences themselves were both associated with resource use. Standardized adjusted hospital resource consumption, expressed as average cost in dollars during the enrollment hospitalization, was lowest when the physician agreed with the patient preference for a do-not-resuscitate order (

Medical Care Inconsistent with Patients' Treatment Goals: Association with 1-Year Medicare Resource Use and Survival

20,527), and highest when the patient did not have a preference and the physician believed the patient wanted resuscitation in the case of a cardiopulmonary arrest (

Physician Understanding Of Patient Resuscitation Preferences: Insights and Clinical Implications

34,829) Hospital resource use was intermediate when patient—physician pairs evidenced either lack of agreement or communication, or awareness of options about resuscitation.CONCLUSIONS: Both physician and patient preferences for CPR influence total hospital resource consumption. Physician misunderstanding of patient preferences to forgo CPR was associated with increased use of hospital resources, and could have led to a course of care at odds with patients’ expressed preferences in the event of cardiac arrest. Increasing physicians’ knowledge of patient preferences, and increasing communication to help patients understand that options foi medical care that include forgoing resuscitation efforts, might reduce hospital expenditures for the seriously ill.

Quantile regression and restricted cubic splines are useful for exploring relationships between continuous variables

To describe how frequently seriously ill persons perceive that the care they receive is inconsistent with treatment preferences and the effect on 1‐year resource utilization.

Rethinking fundamental assumptions : SUPPORT's implications for future reform

OBJECTIVE: To describe physician understanding of patient preferences concerning cardiopulmonary resuscitation (CPR) and to assess the relationship of physician understanding of patient preferences with do not resuscitate (DNR) orders and in‐hospital CPR.

Prognostic Value of Dobutamine Stress Echocardiography in Patients Referred Because of Suspected Coronary Artery Disease

OBJECTIVE Ordinary least squares (OLS) regression, commonly called linear regression, is often used to assess, or adjust for, the relationship between a continuous independent variable and the mean of a continuous dependent variable, implicitly assuming a linear relationship between them. Linearity may not hold, however, and analyzing the mean of the dependent variable may not capture the full nature of such relationships. Our goal is to demonstrate how combined use of quantile regression and restricted cubic splines (RCS) can reveal the true nature and complexity of relationships between continuous variables. STUDY DESIGN AND SETTING We provide a review of methodologic concepts, followed by two examples using real data sets. In the first example, we analyzed the relationship between cognition and disease duration in multiple sclerosis. In the second example, we analyzed the relationship between length of stay (LOS) and severity of illness in the intensive care unit (ICU). RESULTS In both examples, quantile regression showed that the relationship between the variables of interest was heterogeneous. In the second example, RCS uncovered nonlinearity of the relationship between severity of illness and length of stay. CONCLUSION Together, quantile regression and RCS are a powerful combination for exploring relationships between continuous variables.

The effect of patient gender on the prevalence and recognition of alcoholism on a general medicine inpatient service

BACKGROUND: The intervention in SUPPORT, the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments, was ineffective in changing communication, decision‐making, and treatment patterns despite evidence that counseling and information were delivered as planned. The previous paper in this volume shows that modest alterations in the intervention design probably did not explain the lack of substantial effects.

A risk-benefit analysis of elective bilateral oophorectomy: Effect of changes in compliance with estrogen therapy on outcome

To determine whether dobutamine stress echocardiography (DSE) provides prognostic information beyond that available from routine clinical data, we reviewed the outcome of 210 consecutive patients referred for DSE to evaluate chest pain, perioperative risk, and myocardial viability. Dobutamine was infused in increments of 10 micrograms/kg/min in 5-minute stages to a maximum of 40 micrograms/kg/min. The dobutamine stress echocardiogram was considered abnormal only if dobutamine induced a new wall motion abnormality as determined by review of the digitized echocardiographic images in a quad screen format and on videotape. Thirty percent of tests were abnormal. An abnormal test was more common (p < or = 0.02) in men and patients with angina pectoris, in patients taking nitrate therapy, or those with prior myocardial infarction or abnormal left ventricular wall motion at rest. Twenty-two deaths, 17 of which were cardiac, occurred over a median follow-up of 240 days (range 30 to 760). Sixteen cardiac deaths occurred in the 63 patients with versus 1 cardiac death among the 147 without a new wall motion abnormality (p < or = 0.0001). Other variables associated with cardiac death (p < or = 0.05) were age > 65 years, nitrate therapy, ventricular ectopy during DSE, suspected angina pectoris, and hospitalization at the time of DSE. When cardiac death, myocardial infarction, and revascularization procedures were all considered as adverse outcomes, a new wall motion abnormality continued to be the most powerful predictor of an adverse cardiac event.(ABSTRACT TRUNCATED AT 250 WORDS)