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B J McNeil

Publications and source records attributed to B J McNeil.

At least 19 recordsLinked to original sources
PubMed2000

Survival after acute myocardial infarction in patients with end-stage renal disease: results from the cooperative cardiovascular project.

Cardiovascular disease (CVD) is the most common cause of death in patients with end-stage renal disease (ESRD). The optimal management strategy in this population is unknown. We studied 640 patients with ESRD and acute myocardial infarction during 1994 to 1995 as part of the Health Care Financing Administration's Cooperative Cardiovascular Project. The majority of patients were treated with medical therapy alone, 46 patients (7%) were treated with percutaneous transluminal coronary angioplasty (PTCA), and 29 patients (5%) underwent coronary artery bypass grafting (CABG). Patient characteristics and comorbid conditions were similar among the three groups. The overall 1-year mortality rate was 53%. Advanced age, low or high body mass index, history of peripheral vascular disease or stroke, the inability to walk independently, and several indicators of cardiac dysfunction were associated with an increased relative risk (RR) for death. Survival curves differed significantly by treatment modality, with 1-year survival rates of 45%, 54%, and 69% in the medical therapy alone, PTCA, and CABG groups, respectively (P = 0.03). After adjustment for confounding variables, the RR for death was less (but not significantly so) in the CABG group (RR, 0.6; 95% confidence interval, 0.3 to 1.1). There are no randomized clinical trial data to guide therapy of CVD in patients with ESRD. On the basis of these and other available data, CABG may be the optimal therapy for CVD in ESRD. In light of the exceptionally poor outcomes observed for patients treated with medical therapy alone, it may be premature to dismiss PTCA as a therapeutic option in this population.

Age Factors↗
PubMed2000

Staging of advanced ovarian cancer: comparison of imaging modalities--report from the Radiological Diagnostic Oncology Group.

PURPOSE: To compare ultrasonography (US), magnetic resonance (MR) imaging, and computed tomography (CT) for diagnosing and staging advanced ovarian cancer. MATERIALS AND METHODS: US, CT, and MR imaging were performed in 280 patients. Images were read by three radiologists from each of the five hospitals. Image analysis included determination of malignancy within the peritoneum (11 sites), lymph nodes (10 sites), and hepatic parenchyma. The standard of reference was based on surgical and histopathologic findings. Statistical methods used were receiver operating characteristic (ROC) curve analysis, pairwise comparison of areas under the ROC curves (A(z)), analysis of sensitivity and specificity pairs, and assessment of agreement between the degree of suspicion and standard of reference. RESULTS: There were 118 patients with malignant tumors; 73 (62%) had stage III or IV disease. Metastases were found in the peritoneum in 70 (59%), nodes in 20 (17%), and liver in seven (6%) cases. In the peritoneum, MR imaging and CT (A(z) = 0.96 for both) were more accurate than US (A(z) = 0.86), especially in the subdiaphragmatic spaces and hepatic surfaces. MR imaging and CT were more sensitive than US (95%, 92%, and 69%, respectively) for peritoneal metastases. MR imaging was more accurate than CT for detection of lymph node metastases (A(z) = 0.76 vs 0.57, P =.04). In the liver, the A(z) values for the three modalities were 0.77-0.94. CONCLUSION: CT and MR imaging are equally accurate, and either modality can be used to stage advanced ovarian cancer.

Adult↗
PubMed1999

Understanding variability in physician ratings of the appropriateness of coronary angiography after acute myocardial infarction.

We examined variability in ratings of the appropriateness of coronary angiography for 890 clinical scenarios (indications) after an acute myocardial infarction (AMI) from a nine-member multispecialty panel as a function of panel characteristics and the attributes of the clinical indications. We documented a substantial degree of reliability in the ratings. However, key differences among the experts in terms of both their overall propensity to score high and their beliefs regarding the impact of clinical factors on appropriateness were identified. Age, cardiac complications, post-AMI angina, and noninvasive test results were the clinical factors most strongly related to appropriateness ratings for coronary angiography. Further research on the effectiveness of coronary angiography in older patients and in patients with shock, pulmonary edema, and silent ischemia is needed to improve our knowledge about the appropriateness of this procedure in these patients.

Aged↗
PubMed1999

Diagnosis and staging of ovarian cancer: comparative values of Doppler and conventional US, CT, and MR imaging correlated with surgery and histopathologic analysis--report of the Radiology Diagnostic Oncology Group.

PURPOSE: To determine the optimal imaging modality for diagnosis and staging of ovarian cancer. MATERIALS AND METHODS: Two hundred eighty women suspected to have ovarian cancer were enrolled in a prospective study before surgery. Doppler ultrasonography (US), computed tomography (CT), and magnetic resonance (MR) imaging were used to evaluate the mass; conventional US, CT, and MR imaging were used to stage spread. RESULTS: All three modalities had high accuracy (0.91) for the overall diagnosis of malignancy. In the ovaries, the accuracy of MR imaging (0.91) was higher than that of CT and significantly higher than that of Doppler US (0.78). In the extraovarian pelvis and in the abdomen, conventional US, CT, and MR imaging had similar accuracies (0.87-0.95). In differentiation of disease confined to the pelvis from abdominal spread, the specificity of conventional US (96%) was higher than that of CT and significantly higher than that of MR imaging (88%), whereas the sensitivities of MR imaging (98%) and CT (92%) were significantly higher than that of conventional US (75%). CONCLUSION: MR imaging is superior to Doppler US and CT in diagnosis of malignant ovarian masses. There is little variation among conventional US, CT, and MR imaging as regards staging.

Adult↗
PubMed1998

Rating the appropriateness of coronary angiography--do practicing physicians agree with an expert panel and with each other?

BACKGROUND: Evaluations of the appropriateness of medical care are important to monitor the quality of care and to contain costs and enhance safety by reducing inappropriate care. Experts' views are usually incorporated into evaluations of appropriateness. However, practicing physicians may not concur with these views, and physicians' clinical backgrounds may influence their beliefs. METHODS: We asked 1058 internists, family practitioners, and cardiologists in California, Florida, New York, Pennsylvania, and Texas to rate the appropriateness of coronary angiography after acute myocardial infarction for 20 common indications. Nine clinical experts also rated these indications using an established consensus method. RESULTS: For 17 of the 20 indications, median ratings of surveyed physicians and the expert panel agreed within 1 unit on a 9-unit scale. Patients' older age had a negative effect on ratings by the expert panel but not on ratings by surveyed physicians. In multivariable analyses of surveyed physicians, cardiologists rated angiography as significantly more appropriate than did primary care physicians for complicated indications, and for uncomplicated indications cardiologists who performed invasive procedures gave higher appropriateness ratings for angiography than did cardiologists who did not perform such procedures and primary care physicians. For uncomplicated indications, physicians from hospitals providing coronary angioplasty and bypass surgery rated angiography as more appropriate than physicians from other hospitals. Physicians from New York and those employed by health maintenance organizations rated angiography as less appropriate than other physicians. CONCLUSIONS: Surveyed physicians agreed with clinical experts about the appropriateness of coronary angiography after myocardial infarction for most indications, indicating that well-designed expert panels can closely reflect the views of practicing physicians. Variations in beliefs among practicing physicians suggest that evaluations of medical practice should incorporate the views of a range of relevant types of physicians.

Aged↗
PubMed1998

Rate of insufficient samples for fine-needle aspiration for nonpalpable breast lesions in a multicenter clinical trial: The Radiologic Diagnostic Oncology Group 5 Study. The RDOG5 investigators.

BACKGROUND: Radiologic Diagnostic Oncology Group 5 is a multicenter clinical trial designed to evaluate fine-needle aspiration (FNA) of nonpalpable breast lesions performed by multiple operators using the same protocol. METHODS: Four hundred and nineteen women with mammographically detected nonpalpable breast lesions were enrolled on the trial at 18 institutions. Group A institutions randomized women to stereotactically guided FNA (SFNA) followed by stereotactically guided core needle biopsy (SCNB), or SCNB only. Group B institutions randomized women to SFNA and SCNB, SCNB, or ultrasonographically guided FNA followed by ultrasonographically guided core needle biopsy (USCNB), or USCNB only. A total of 377 women were eligible for analysis. RESULTS: FNA yielded 128 insufficient samples for the 377 patients (33.95%; 95% confidence interval, 29.2-38.7%). The rate of insufficient samples varied by type of lesion with calcified lesions associated with a significantly higher rate of insufficient sampling than masses (P < 0.001). The radiologist's level of suspicion of the lesion was not a statistically significant predictor of insufficient samples for mass lesions, but was a predictor for calcified lesions. For the 336 lesions for which histologic information was available, insufficient samples occurred in significantly more benign than malignant lesions. CONCLUSIONS: The high rate of insufficient samples for FNA of nonpalpable breast lesions in this multicenter trial makes its use impractical in this setting. Because of this factor, the study was terminated early.

Adult↗
PubMed1998

Eliciting expert opinion using the Delphi technique: identifying performance indicators for cardiovascular disease.

Combining opinion from expert panels is becoming a more common method of selecting criteria to define quality of health care. The Rand Corporation pioneered this method is the 1950s and 1960s in the context of forecasting technological events. Since then, numerous organizations have adopted the methodology to develop local and national policy. In the context of quality of care, opinion is typically elicited from a sample of experts regarding the appropriateness or importance of a medical treatment for several well-defined clinical cohorts. The information from the experts is then combined in order to create a standard or performance measure of care. This article describes how to use the panel process to elicit information from diverse panels of experts. Methods are demonstrated using the data from five distinct panels convened as part of the Harvard Q-SPAN-CD study, a nationally-funded project whose goal is to identify a set of cardiovascular-related performance measures.

Boston↗
PubMed1998

Comparison of CT and MR imaging in staging of neck metastases.

PURPOSE: To compare the abilities of magnetic resonance (MR) imaging and computed tomography (CT) in detection of lymph node metastasis from head and neck squamous cell carcinoma. MATERIALS AND METHODS: MR imaging and CT were performed with standard protocols in patients with known carcinoma of the oral cavity, oropharynx, hypopharynx, or larynx. Histopathologic examination was performed to validate imaging findings. Between 1991 and 1994, 213 patients undergoing 311 neck dissections were accrued at three institutions. RESULTS: For the upper jugular and spinal accessory regions, the areas under the receiver operating characteristic curves for combined information on size and internal abnormality were 0.80 for CT and 0.75 for MR imaging. Sensitivities, specificities, negative predictive values (NPVs), and positive predictive values (PPVs) were calculated for various size criteria with and without internal abnormality information. With use of a 1-cm size or an internal abnormality to indicate a positive node, CT had an NPV of 84% and a PPV of 50%, and MR imaging had an NPV of 79% and a PPV of 52%. CT achieved an NPV of 90%, correlating with a PPV of 44%, with use of 5-mm size as an indicator of a positive node. CONCLUSION: CT performed slightly better than MR imaging for all interpretative criteria. However, a high NPV was achieved only when a low size criterion was used and was therefore associated with a relatively low PPV.

Adolescent↗
PubMed1997

Use of cardiac procedures and outcomes in elderly patients with myocardial infarction in the United States and Canada.

BACKGROUND: Acute myocardial infarction is a leading cause of morbidity and mortality in the United States and Canada. We performed a population-based study to compare the use of cardiac procedures and outcomes after acute myocardial infarction in elderly patients in the two countries. METHODS: We compared the use of invasive cardiac procedures and the mortality rates among 224,258 elderly Medicare beneficiaries in the United States and 9444 elderly patients in Ontario, Canada, each of whom had a new acute myocardial infarction in 1991. RESULTS: The U.S. patients were significantly more likely than the Canadian patients to undergo coronary angiography (34.9 percent vs. 6.7 percent, P< 0.001), percutaneous transluminal coronary angioplasty (11.7 percent vs. 1.5 percent, P<0.001), and coronary-artery bypass surgery (10.6 percent vs. 1.4 percent, P<0.001) during the first 30 days after the index infarction. These differences in the use of cardiac procedures narrowed but persisted through 180 days of follow-up. The 30-day mortality rates were slightly but significantly lower for the U.S. patients than for the Canadian patients (21.4 percent vs. 22.3 percent, P=0.03). However, the one-year mortality rates were virtually identical (34.3 percent in the United States vs. 34.4 percent in Ontario, P= 0.94). CONCLUSIONS: Short-term mortality after an acute myocardial infarction was slightly lower in the United States than in Ontario, but these differences did not persist through one year of follow-up. The strikingly higher rates of use of cardiac procedures in the United States, as compared with Canada, do not appear to result in better long-term survival rates for elderly U.S. patients with acute myocardial infarction.

Aged↗
PubMed1997

Coronary artery bypass graft surgery in Ontario and New York State: which rate is right? Steering Committee of the Cardiac Care Network of Ontario.

BACKGROUND: Previous studies have shown that the rate of coronary artery bypass graft (CABG) surgery is much higher in New York State than in Ontario. OBJECTIVE: To compare the service context and clinical characteristics of patients having CABG surgery in New York and Ontario. DESIGN: Retrospective analysis of data from cardiac surgery registries in New York and Ontario. PATIENTS: All 16,690 patients in New York and 5517 patients in Ontario who had isolated CABG surgery in 1993. MEASUREMENTS: Clinical characteristics of patients having CABG surgery and rates of CABG surgery by coronary anatomy. RESULTS: The overall age-adjusted rate of isolated CABG surgery was 1.79 times (95% CI, 1.74 to 1.85) greater in New York than in Ontario. Patients who had CABG surgery in New York were more likely to be elderly and female and to have recently had myocardial infarction (P < 0.001), whereas patients who had CABG surgery in Ontario were more likely to have had left ventricular dysfunction and severe coronary artery disease (two-vessel disease with proximal left anterior descending disease, three-vessel disease, or left main disease) (P < 0.001). The relative rate of CABG surgery for left main disease was 2.53 times (CI, 2.35 to 2.73) greater in New York than in Ontario but was 8.97 times (CI, 8.01 to 10.06) greater for patients with limited coronary artery disease (one-vessel or two-vessel disease without proximal left anterior descending disease). CONCLUSIONS: The higher rates of CABG surgery in New York are associated with higher rates of CABG surgery among the elderly, women, and patients who recently had myocardial infarction. Potential underservicing in Ontario is suggested by a lower rate of CABG surgery for left main disease; however, the higher rate of CABG surgery in New York is also associated with a strikingly higher rate of surgery in patients with limited coronary disease. Such trade-offs highlight the difficulty of defining an optimal rate of CABG surgery.

Adult↗
PubMed1997

Staging prostate cancer with MR imaging: a combined radiologist-computer system.

PURPOSE: To test the accuracy of a combined radiologist-computer system in the diagnosis with magnetic resonance (MR) imaging of cancer of the prostate gland. MATERIALS AND METHODS: The combined system was developed and tested by four specialists in prostate MR imaging and five radiologists expert in body MR imaging. Each group read MR images obtained in 100 proved cases of prostate cancer. The images were obtained from two sources, and all were obtained with an endorectal surface coil. Prostate MR specialists ranked imaging features of cases to develop a checklist for image interpretation. Features with greatest diagnostic value were incorporated in the combined system. Accuracy measures were derived from the area index of the receiver operating characteristic curve for the combined system and compared with those of radiologists working alone. RESULTS: Body MR radiologists had a mean baseline accuracy of 0.67; mean accuracy of their combined system was 0.80. The prostate MR specialists, when they rated the features in each case, had a mean accuracy of 0.81; the accuracy of their combined system was 0.87. CONCLUSIONS: A combined radiologist-computer system substantially improved accuracy of body MR radiologists in the diagnosis of prostate cancer. High levels of accuracy were also achieved by the system with prostate MR specialists.

Diagnosis, Computer-Assisted↗
PubMed1997

CT and MR imaging in the local staging of primary malignant musculoskeletal neoplasms: Report of the Radiology Diagnostic Oncology Group.

PURPOSE: To assess the relative accuracies of computed tomography (CT) and magnetic resonance (MR) imaging in the local staging of primary malignant bone and soft-tissue tumors. MATERIALS AND METHODS: At four institutions, 367 eligible patients (aged 6-89 years) with malignant bone or soft-tissue neoplasms in selected anatomic sites were enrolled. Patients underwent both CT and MR imaging within 4 weeks before surgery. In each patient, CT scans were interpreted independently by two radiologists and MR images by two other radiologists at the enrolling institution. The CT and MR images were then interpreted together by two of those radiologists and subsequently reread at the other institutions. Imaging and histopathologic findings were compared and were supplemented when needed with surgical findings. Receiver operating characteristic curve analysis and descriptive statistical analysis were performed. RESULTS: Cases were analyzable in 316 patients: 183 had primary bone tumors; 133 had primary soft-tissue tumors. There was no statistically significant difference between CT and MR imaging in determining tumor involvement of muscle, bone, joints, or neurovascular structures. The combined interpretation of CT and MR images did not statistically significantly improve accuracy. Interreader variability was similar for both modalities. CONCLUSION: CT and MR imaging are equally accurate in the local staging of malignant bone and soft-tissue neoplasms in the specific anatomic sites studied.

Adolescent↗
PubMed1997

Rapid method for rigorous assessment of radiologic imaging technologies.

Rapid and rigorous technology evaluation is important for improving quality and cost in health care, particularly for swiftly changing, highly technologic fields like radiology. Currently, however, evaluations are generally seriously deficient in quality, and rigorous evaluations typically require 4 years or more. Therefore, the authors developed an appropriate methodology. Its principal characteristics include study of outcomes, clinical relevance, multi-institutional design, intensive communication, experienced data management and statistical centers, sophisticated analysis, careful attention to the protocol and reference standard, on-site managers, and extensive pretesting and refinement. The authors successfully tested the methodology in a seven-institution study. Completed in 1 1/4 years, the study achieved active participation of treating physicians, which much enhanced the clinical relevance of the end points studied. The data supported extensive analyses, which included the effect of imaging on treatment plans, an important outcome measure. The authors report the (limited) difficulties encountered and identify changes to ameliorate them. Thus revised, the methodology can serve as a model for future technology assessments.

Technology Assessment, Biomedical↗
PubMed1997

Prostate cancer: relative effects of demographic, clinical, histologic, and MR imaging variables on the accuracy of staging.

PURPOSE: To determine the effects on the accuracy of staging prostate gland cancer of diagnostic prediction rules based on demographic, clinical, histologic, and magnetic resonance (MR) image variables. MATERIALS AND METHODS: A total of 200 cases from four medical centers were evaluated by nine radiologists experienced in MR imaging. The accuracies of the four diagnostic variables (age, prostate specific antigen level, Gleason tumor grade, and MR imaging findings) were measured, both singly and combined in a particular sequence, by calculating the area index of the receiver operating characteristic curve. RESULTS: The accuracy of staging with single variables (age, 0.58; prostate specific antigen level, 0.74; Gleason grade 0.73, MR image findings, 0.74) increased as the variables were optimally merged. The first two variables combined to yield an accuracy of 0.74; the first three combined to yield an accuracy of 0.81; and all four variables resulted in an accuracy of 0.86. In a clinically important subset of 69 cases for which antigen level and Gleason grade together were inconclusive for the purposes of staging, the addition of MR imaging findings resulted in an increase in accuracy from 0.55 to 0.73. CONCLUSION: Optimal merging of diagnostic test results yields an improvement in the accuracy of prostate cancer staging.

Age Factors↗
PubMed1996

Using admission characteristics to predict short-term mortality from myocardial infarction in elderly patients. Results from the Cooperative Cardiovascular Project.

OBJECTIVE: To develop a prediction model of death within 30 days of hospital admission for Medicare patients with acute myocardial infarction that would permit use of risk-adjusted mortality rates as hospital quality measures. DESIGN: Retrospective cohort study using data created from medical charts and administrative files. SETTING: All acute care hospitals in Alabama, Connecticut, Iowa, or Wisconsin. PATIENTS: A cohort of 14,581 patients with acute myocardial infarction covered by Medicare in 1993. RESULTS: The unadjusted 30-day mortality rate was 21%, ranging from 18% in Connecticut to 23% in Alabama. The 4 largest contributors to variability in mortality rates were mean arterial pressure, age, respiratory rate, and serum urea nitrogen level. The area under the receiver operator characteristic curve was 0.79 in a developmental sample of 10 936 patients and 0.78 in a validation sample of 3645 patients. Based on admission variables, we were able to explain 27% of the variability in 30-day mortality rates. During the index admission, aspirin, beta-blockers, angiotensin-converting enzyme inhibitors, and thrombolytic agents were used in 72%, 39%, 32%, and 15% of patients, respectively. Explained variation increased by 6 percentage points to 33% when drug therapies and revascularization procedures performed during the index admission were added to the model predictors. CONCLUSIONS: Short-term mortality remains high for elderly patients with acute myocardial infarction, and a large percentage of variation remains unexplained after controlling for admission severity. Part of the unexplained variability can be explained by the location of the admitting hospital; some of the remaining unexplained variation may reflect differences in quality of care or unmeasured differences in disease severity. Researchers should develop quality indicators based on process measures for acute myocardial infarction and should incorporate these measures into mortality models to determine whether quality accounts for variation in 30-day mortality rates beyond that explained by clinical status at admission.

Aged↗