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Biomedical subjects

R F Nease

Publications and source records attributed to R F Nease.

At least 37 records · Page 2Linked to original sources

The effect of an educational intervention on the perceived risk of breast cancer.

OBJECTIVE: To appraise women's perceived risk of developing breast cancer and the effects of a physician's educational intervention on this perception. DESIGN: Longitudinal before-and-after study involving four measures of participants risk of developing breast cancer. Eligible women provided the data needed to calculate an objective estimate of their individual risk of developing breast cancer before age 80 using the Gail formula. They also provided a subjective estimate of their individual perceived risk. Then, each participant met with a general internal medicine physician who provided personalized information and education. Immediately after education, and again several months later, we reassessed each woman's perceived risk. SETTING: Physicians office. PARTICIPANTS: A convenience sample of 59 women participating in the Tamoxifen Breast Cancer Prevention Trial. Twenty-nine women returned for the follow-up risk assessment. MEASUREMENTS AND MAIN RESULTS: The median calculated risk of breast cancer before age 80 (by the Gail formula) was 15%, but the median perceived risk before educational intervention was 50%. The perceived risk after educational intervention fell to 25%. At late follow-up, the median perceived risk remained at 25%. The difference between the preeducational perceptions and the calculated estimates was significant (1) < .0001). After educational intervention, perceived risk measures shifted closer to the calculated value, but still remained significantly higher (p <.0001). CONCLUSIONS: Women often substantially overestimate their chances of getting breast cancer. Educational intervention by a physician, including explanation of an individual's calculated risk, can reduce this error. The effect of education appears to persist at least for several months.

Adult↗

The importance of patient preference in the decision to screen for prostate cancer. Prostate Patient Outcomes Research Team.

OBJECTIVE: Routine screening for prostate cancer is controversial because of frequent false-positive results, the potential for slow, non-life-threatening growth of untreated cancer, the uncertainty regarding whether treatment can extend life, and the potential for treatment complications. This study examines how information about prostate-specific antigen (PSA) testing and the uncertain benefits of treating prostate cancer affects patients' desire for PSA testing. DESIGN: An educational videotape designed to inform men about the uncertainty surrounding PSA screening and the treatment of early-stage prostate cancer was presented to two groups of male patients 50 years of age or older. SETTING: Dartmouth-Hitchcock Medical Center. PATIENTS/PARTICIPANTS: For study 1, men seeking a free prostate cancer screening were preassigned to view the educational videotape (N = 184) or another videotape (N = 185). For study 2, men scheduled to visit a general internal medicine clinic viewed either the educational videotape (N = 103) or no videotape (N = 93). MEASUREMENTS AND MAIN RESULTS: The men's information and preferences about prostate cancer screening and treatment and actual choice of PSA test at the next test opportunity were measured. Men who viewed the educational videotape were: better informed about PSA tests, prostate cancer, and its treatment; preferred no active treatment if cancer were found; and preferred not to be screened (all significant at p < or = .002 in both studies). Men viewing the educational video were less likely to have a PSA test (p = .041, study 2). This tendency was not significant at the free-PSA clinic (p = .079). CONCLUSIONS: Preference regarding cancer screening and treatment is greatly affected by information about medical uncertainties. Because informed patient choices vary. PSA screening decisions should incorporate individual preferences.

Case-Control Studies↗

Perceptions of breast cancer risk and screening effectiveness in women younger than 50 years of age.

BACKGROUND: The National Cancer Institute has recently changed its approach and has substituted summary-of-evidence statements for specific recommendations for breast cancer screening in women 40-50 years of age, leaving these women with a greater share of decision-making responsibility. To make an informed decision about breast cancer screening, women need accurate information about their breast cancer risk and the benefit of screening. Although it has been suggested that women younger than 50 years of age overestimate this risk and benefit, their estimates have not been quantified. PURPOSE: The purpose of this study was to determine how women 40-50 years of age perceive their risk of breast cancer and the effectiveness of screening and how these perceptions compare with estimates derived from epidemiologic studies of breast cancer incidence and randomized clinical trials of screening. METHODS: We mailed a questionnaire to 200 women, identified through the computerized medical records of Dartmouth-Hitchock Medical Center, who were between 40 and 50 years of age and had no history of breast cancer. Each woman was asked about her risk factors for breast cancer and asked to estimate her probabilities of developing breast cancer and dying of it within 10 years, with and without screening. The women's answers were compared with individual probabilities derived from the Gail et al. model, age-specific probabilities of developing and dying of breast cancer in the United States, and the results of randomized clinical trials of screening. RESULTS: The mailed questionnaire was completed and returned by 145 (73%) of the 200 women. Respondents over-estimated their probability of dying of breast cancer within 10 years by more than 20-fold (median, 22.3; interquartile range, 11.1-74.2). Assuming a 10% relative risk reduction from screening, respondents overestimated the relative risk reduction by sixfold (median, 6.0; interquartile range, 5.0-7.5) and the absolute risk reduction more than 100-fold (median, 127.5; interquartile range, 47.1-399.6). The median perceived estimate of absolute risk reduction was 6.0 breast cancer deaths per 100 women; the median calculated estimate was only 0.04 per 100 women. CONCLUSION: These findings suggest that many women younger than 50 years of age substantially overestimate their breast cancer risk and the effectiveness of screening. IMPLICATIONS: A balanced presentation of information about breast cancer risk and screening effectiveness may improve decision making for women younger than 50 years of age and reduce their anxiety about breast cancer, regardless of whether they choose to be screened.

Adult↗

Screening surgeons for HIV infection. A cost-effectiveness analysis.

UNLABELLED: OBJECTIVE. To determine the cost-effectiveness of a policy to screen surgeons for human immunodeficiency virus (HIV) infection to prevent transmission of HIV to patients having invasive procedures. DESIGN: Cost-effectiveness analysis. RESULTS: A one-time national screening program would identify approximately 137 surgeons with HIV infection (range, 28 to 423 surgeons) and would prevent approximately 4.3 infections (range, 1.9 to 21.3 infections) in patients treated by infected surgeons and 0.9 infections (range, 0 to 12.9 infections) in sexual partners of infected surgeons at a direct cost of $8.1 million and an induced cost of approximately $44 million. It would result in expenditures of $458,000 per year of life saved (range, $147,000 to $687,000 per year of life saved), whereas an annual screening program would result in expenditures of approximately $1.1 million per year of life saved (range, $338,000 to $1,886,000 per year of life saved). If the prevalence of HIV infection in surgeons is estimated to be three times our base-case estimate (an increase from 0.1% to 0.3%), annual screening would result in expenditures of approximately $741,000 per year of life saved. If the probability of seroconversion after a patient is exposed to a contaminated instrument is increased to 5.0% from our base-case estimate of 0.29%, an annual screening program would still cost more than $228,000 per year of life saved. CONCLUSION: Screening surgeons for HIV to prevent transmission of HIV to patients having invasive procedures requires expenditures per year of life saved that are considerably in excess of those of most accepted health interventions. Surveillance studies of patients treated by surgeons infected with HIV should be continued to confirm that transmission of HIV to patients having invasive procedures is rare.

Cost-Benefit Analysis↗

Variation in patient utilities for outcomes of the management of chronic stable angina. Implications for clinical practice guidelines. Ischemic Heart Disease Patient Outcomes Research Team.

OBJECTIVE: Although practice guidelines sometimes make recommendations based on symptom severity, they rarely account for how patients feel about their symptoms. To investigate the possible importance of patient preferences in treatment of ischemic heart disease, we assessed attitudes toward symptoms in patients with angina pectoris. DESIGN: Case series. SETTING: Ambulatory cardiology clinics at two tertiary care medical centers. PATIENTS: A total of 220 subjects were selected from 589 patients with chronic stable angina referred from cardiologists to achieve patients samples balanced for sex, race, and angina severity. MAIN OUTCOME MEASURES: We measured patients' attitudes toward their angina using the rating scale, time trade-off, and standard gamble utility metrics. Reliability of measurements was evaluated by repeating the assessments 2 weeks later on 50 willing patients. RESULTS: While the mean responses followed the expected patterns (those with more severe Canadian Cardiovascular Society scores chose lower utilities), attitudes toward symptoms varied substantially among patients with similarly severe angina. For example, there was a 33% chance that a patient with class II angina had a time trade-off utility that was lower (ie, more bothered by symptoms) than a patient with more severe angina (class III/IV). This variation in utilities was not due to random error in the assessments. CONCLUSIONS: Angina patients with similar functional limitation vary considerably in their tolerance for their symptoms, as measured by utilities. Our findings suggest that guidelines for the management of ischemic heart disease should be based on the preferences of the individual patient rather than on symptom severity alone.

Adult↗

Patient desire for information and decision making in health care decisions: the Autonomy Preference Index and the Health Opinion Survey.

OBJECTIVES: To compare results on the Autonomy Preference Index (API) and the Health Opinion Survey (HOS), two instruments that measure patient desire for information and involvement in decision making. DESIGN: Cross-sectional survey. SETTING: University-based primary care outpatient longitudinal and acute care clinic. PATIENTS: 167 patients with benign prostatic hyperplasia, back pain, or mild hypertension seen from October 1991 to December 1992. MEASUREMENTS AND MAIN RESULTS: On the API and the HOS (both scaled from 0 to 1), the patients had intermediate desire for involvement in decision making (median API: 0.42; HOS: 0.36) and higher desire for information (median API: 0.97; HOS: 0.57). With either instrument, the desire for information exceeded that for involvement in decision making (p < 0.0001). The API information scores were higher than the HOS information scores (p < 0.0001), probably because the HOS focuses on patient behavior rather than desire. Variation in desire for information and involvement in decision making was substantial and largely unexplained. CONCLUSIONS: Most patients have a high desire for information, the desire for information and involvement in decision making varies substantially among patients, and the API is preferable to the HOS for researchers interested in focusing solely on patient desire for information.

Adult↗

The decision to enter a randomized trial of tamoxifen for the prevention of breast cancer in healthy women: an analysis of the tradeoffs.

OBJECTIVE: Interest in breast cancer prevention has led to the Breast Cancer Prevention Trial (BCPT), a controversial randomized trial of tamoxifen for women at risk for breast cancer. The goal of our study was to determine whether the potential benefits of enrolling in the randomized trial of prophylactic tamoxifen outweigh the potential risks. METHODS: We used a decision analytic model based on the available data on tamoxifen treatment benefits in women with breast cancer and extrapolated to its use in healthy women. RESULTS: For a 50-year-old woman with a breast cancer risk twice that of the average woman her age, the BCPT offers an increase in life expectancy of about 9 days, a gain that is modest compared with other health interventions. For women ages 35 to 60 who meet the minimum risk of breast cancer for trial eligibility, the trial increases life expectancy by about 8 or 9 days. Assumptions about the effect of tamoxifen on the incidence of endometrial and liver cancer and on quality of life associated with tamoxifen did not alter our findings. CONCLUSIONS: Advocates and opponents of the BCPT should temper their concerns to reflect the modest absolute benefits and harms associated with the trial. Although women at increased risk for breast cancer should be aware of the likely overall benefit associated with entry into the trial, for most women, entry into the BCPT is unlikely to alter substantially their length of life, in either a beneficial or harmful manner.

Adult↗

Assessing the preferences of patients with psoriasis. A quantitative, utility approach.

BACKGROUND AND DESIGN: Patient preferences for health outcomes can be explicitly assessed and expressed in quantitative terms known as utilities. Three standard methods for utility assessment have been used to quantify patient preferences, but these methods have not previously been applied to skin disease. Eighty-seven patients with psoriasis from a tertiary medical center were interviewed, using an interactive, computer-based utility assessment questionnaire, U-Titer. Utilities for three categories of psoriasis severity and potential adverse outcomes of methotrexate therapy were assessed by the vertical rating scale, time trade-off, and standard gamble. RESULTS: Patients assigned a broad range of utilities for each of the health states. Utilities obtained by the vertical rating scale did not correlate well with utilities obtained by standard gamble or time trade-off methods. However, utilities assessed by standard gamble and time trade-off were not significantly different. Patient characteristics such as age, gender, and education were not correlated with utility and did not explain the variation. Indicators of the patients' disease severity were not predictive of utilities for the assessed health states. The relatively high utility for liver biopsy suggests that there is less patient aversion to the procedure than suspected. CONCLUSIONS: Utilities, or quantitative measures of patient preferences for health states, are measurable and vary widely for mild, moderate, and severe psoriasis and possible adverse outcomes of methotrexate treatment. The process of elucidating individual patient utilities for various health outcomes can be used to incorporate patient preferences into the process of clinical decision making. Guidelines that are based solely on severity of symptoms, without input from patients on how they value such symptoms, must be questioned.

Adult↗

Cost-effectiveness of preoperative autologous donation in coronary artery bypass grafting.

Concern about the safety of the allogeneic blood supply has made preoperative autologous blood donation (PAD) routine before major noncardiac operations. However, the costs and benefits of PAD in elective coronary artery bypass grafting (CABG) are not well established. We used decision analysis to (1) calculate the cost-effectiveness of PAD in CABG, expressed as cost per year of life saved, and (2) compare the health benefits of reducing allogeneic transfusions with the potential risks of autologous blood donation by patients with coronary artery disease. A prospective study of 18 institutions provided data on transfusion practice and blood product costs in CABG. On average, PAD in CABG costs $508,000 to $909,000 per quality-adjusted year of life saved, depending on the number of units donated. Preoperative autologous blood donation is more cost-effective (as low as $518,000 per year of life saved) when targeted to younger patients undergoing CABG at centers with high transfusion rates. The cost-effectiveness of PAD is strongly dependent on estimates of posttransfusion hepatitis incidence, but less so on plausible estimates of the current risk of human immunodeficiency virus transmission. Although the actual risk of PAD is uncertain, even a small fatality risk (> 1 per 101,000 donations) associated with blood donation by patients awaiting CABG negates all life expectancy benefits of PAD. At current costs, PAD by patients awaiting CABG is not cost-effective, producing small health benefits at high societal cost. For the individual patient, the risk of donating blood before CABG may well outweigh the benefits associated with fewer allogeneic transfusions.

Blood Transfusion, Autologous↗

A computer-based interview to identify HIV risk behaviors and to assess patient preferences for HIV-related health states.

We developed a computer-based utility assessment tool to assess the preferences of patients towards HIV-related health states and identify risk behaviors (both sexual and drug related) of the patient being interviewed. The reliability of the computer-based interview was assessed through comparison with person-to-person interviews. Our pilot study included 22 patients. Twelve of these patients were also interviewed by the research assistants in person-to-person interviews. The agreement between the person-to-person and computer-based interviews was excellent (3 discrepancies of 180 compared answers), and the majority of the patients preferred to use the computer to disclose sensitive information regarding risk behaviors. Our study suggests that assessment of patient preferences and risk factors can be performed reliably through a computer-based interview.

Adult↗

Development of outcome-based practice guidelines: a method for structuring problems and synthesizing evidence.

BACKGROUND: The growth in guidance development projects has focused attention on the methods used in developing the guideline. For a guideline to be sound it should be linked on the basis of scientific evidence to the very health outcome that the guideline is designed to promote. METHODS: Structuring a health intervention as an influence diagram, a decision model (1) allows for the identification of the relevant benefits, harms, and costs that may result from an intervention; (2) provides an explicit link between the intervention and these outcomes, a crucial prerequisite for the development of an outcome-based guideline; and (3) identifies the evidence that must be synthesized to predict the effect of the intervention on the health outcomes. EXAMPLE: In the development of a guideline related to prevention of opportunistic infections in HIV-infected persons, we would define the interventions (for example, use of medication for PCP pneumonia), the intended health outcome (a potential reduction in the number of opportunistic infections), and the evidence that demonstrates that the intervention produces the desired outcome. If PCP prophylaxis is delayed, the HIV-infected person is exposed to a undue risk of PCP, with its attendant morbidity and mortality. If it is initiated too early, the person incurs excess monetary costs and may experience additional side-effect-associated morbidity. EXAMPLE: The intervention in question is screening for HIV infection, and the outcomes of interest are the medical benefits and harms associated with screening and the financial costs (and savings) that a screening program would incur. Screening for HIV infection differs from many clinical questions because it has potential benefit both to the persons screened and to public health if the screened person reduces risk behaviors that might transmit HIV infection. CONCLUSIONS: Structuring a problem with an influence diagram: delineates an explicit link between interventions and outcomes; focuses the questions to be addressed (a series of more sharply defined questions, each of which we may be able to answer based on direct evidence, replaces a much broader question [should we screen for HIV?], which cannot be answered directly); and highlights the importance of a clear, unambiguous statement whose benefit and costs are under consideration.

Decision Support Techniques↗

Finding equilibrium in U.S. physician supply.

One essential component of health system reform is to bring the number of physicians in line with the needs of the population. The physician supply policies of prepaid group practice health maintenance organizations have been cited as one model to achieve this goal. Planning for physician supply should be an explicit public-sector activity and should not be left to the private sector, because some areas are not sufficiently populated to support competing providers under a managed competition scheme. A new model for planning for physician supply should include the following strategies: (1) erecting barriers to entry into medical practice; (2) encouraging early retirement; (3) restructuring economic incentives; (4) reallocating physicians to underserved areas in the United States and abroad; and (5) creating new areas of professional responsibility for physicians.

Education, Medical↗

Occupational exposure to human immunodeficiency virus and hepatitis B virus: a comparative analysis of risk.

OBJECTIVE: To estimate the occupational risk from infection with the human immunodeficiency virus (HIV) in terms of loss of (quality-adjusted) life expectancy, and to compare that risk to those posed by other hazards faced by health care workers. DESIGN: Decision-analytic model. RESULTS: For a 30-year-old female health care worker (unvaccinated for hepatitis B virus [HBV]), the loss of life expectancy from a needlestick from a symptomatic HIV-positive (HIV+) patient is 39 days (range, 17 to 93 days), as compared with a loss of 17 days from a needlestick from a patient who is hepatitis-B-surface-antigen-positive (HBsAg+), and 38 days from a needlestick from a patient who is hepatitis-B-e-antigen-positive (HBeAg+). When morbidity is included in the analysis of risk (through calculation of the quality-adjusted loss of life expectancy), the risk from both HBV and HIV increases. The quality-adjusted loss of life expectancy due to a needlestick exposure from a symptomatic HIV+ patient is 45 days (range, 20 to 108 days), as compared with a quality-adjusted loss of life expectancy of 48 days from a needlestick from an HBsAg+ patient, and 109 days from a needlestick from a patient who is known to be HBeAg+. By comparison, a cross-country automobile trip is associated with a loss of life expectancy of approximately 1 day. The 45- to 50-day loss of quality-adjusted life expectancy from percutaneous exposures to HIV and HBV is approximately the same magnitude as the gain in life expectancy from 10 years of annual screening for breast cancer with mammography and physical examination. CONCLUSIONS: The risk associated with percutaneous exposures to symptomatic HIV+ patients is comparable to other risks that health care workers have faced knowingly and have accepted in the recent past. However, the loss of quality-adjusted life expectancy associated with a needlestick exposure is significant. Identification of cost-effective methods that increase the safety of medical personnel but also ensure full access to high-quality care for HIV+ patients should be a high priority.

Acquired Immunodeficiency Syndrome↗

Cost-effectiveness analysis in clinical practice: the case of heart failure.

Heart failure is the leading cause of hospitalization in adults older than 65 years, and it is currently the most costly cardiovascular disorder in the United States, with estimated annual expenditures in excess of $20 billion. Recent studies have shown that selected pharmacological agents, behavioral interventions, and surgical therapies are associated with improved clinical outcomes in patients with heart failure, but the cost implications of these diverse treatment modalities are not widely appreciated. In this review, a brief outline of cost-effectiveness analysis is provided, and current data on the cost-effectiveness of specific approaches to managing heart failure are discussed. Available evidence indicates that angiotensin converting enzyme inhibitors, other vasodilators, digoxin, carvedilol, multidisciplinary heart failure management teams, and heart transplantation are all cost-effective approaches to treating heart failure; moreover, some of these interventions may result in net cost savings.

Angiotensin-Converting Enzyme Inhibitors↗

Design and pilot evaluation of a system to develop computer-based site-specific practice guidelines from decision models.

BACKGROUND: Local tailoring of clinical practice guidelines (CPGs) requires experts in medicine and evidence synthesis unavailable in many practice settings. The authors' computer-based system enables developers and users to create, disseminate, and tailor CPGs, using normative decision models (DMs). METHODS: ALCHEMIST, a web-based system, analyzes a DM, creates a CPG in the form of an annotated algorithm, and displays for the guideline user the optimal strategy. ALCHEMIST'S interface enables remote users to tailor the guideline by changing underlying input variables and observing the new annotated algorithm that is developed automatically. In a pilot evaluation of the system, a DM was used to evaluate strategies for staging non-small-cell lung cancer. Subjects (n = 15) compared the automatically created CPG with published guidelines for this staging and critiqued both using a previously developed instrument to rate the CPGs' usability, accountability, and accuracy on a scale of 0 (worst) to 2 (best), with higher scores reflecting higher quality. RESULTS: The mean overall score for the ALCHEMIST CPG was 1.502, compared with the published-CPG score of 0.987 (p = 0.002). The ALCHEMIST CPG scores for usability, accountability, and accuracy were 1.683, 1.393, and 1.430, respectively; the published CPG scores were 1.192, 0.941, and 0.830 (each comparison p < 0.05). On a scale of 1 (worst) to 5 (best), users' mean ratings of ALCHEMIST'S ease of use, usefulness of content, and presentation format were 4.76, 3.98, and 4.64, respectively. CONCLUSIONS: The results demonstrate the feasibility of a web-based system that automatically analyzes a DM and creates a CPG as an annotated algorithm, enabling remote users to develop site-specific CPGs. In the pilot evaluation, the ALCHEMIST guidelines met established criteria for quality and compared favorably with national CPGs. The high usability and usefulness ratings suggest that such systems can be a good tool for guideline development.

Decision Making, Computer-Assisted↗