Biomedical subjects

E B Bass

Publications and source records attributed to E B Bass.

At least 73 records · Page 4Linked to original sources

PubMed1995

Cataract surgical techniques. Preferences and underlying beliefs.

To characterize the intraoperative procedures employed by cataract surgeons in the United States and the beliefs underlying the practices, a standardized questionnaire was sent to a systematic random sample of members of the American Academy of Ophthalmology in 1992. Of 667 surveyed ophthalmologists, 550 completed the questionnaire (response rate, 82.5%). Phacoemulsification was used for more than 75% of routine cataract surgery by 46% of respondents, whereas standard extracapsular surgery was used for more than 75% of routine cataract surgery by 41% of respondents. Preferential use of phacoemulsification was independently associated with more recent graduation from medical school and higher reported annual surgical volume. Continuous tear capsulotomy was employed by 52% of ophthalmologists. Preference for this technique was independently associated with both the use of phacoemulsification and higher annual surgical volume. Seventy-one percent of respondents used retrobulbar anesthesia, whereas 28% used peribulbar anesthesia. Use of peribulbar anesthesia was independently associated with both greater surgical volume and performance of surgery in an ambulatory surgical center. Beliefs regarding comparative safety and effectiveness were reported to influence surgeons' preferences strongly among all of the competing techniques studied. Those performing phacoemulsification, in comparison with those performing extracapsular cataract extraction, reported that the expectation of reduced astigmatism and shorter recovery time strongly influenced their choice of procedure. Variation in preferred intraoperative techniques is substantial for cataract surgery and the beliefs that underlie the preferences. Such variation highlights the need to determine which techniques maximize patient outcomes and are most cost-effective.

Adult↗

PubMed1995

Do ophthalmologists, anesthesiologists, and internists agree about preoperative testing in healthy patients undergoing cataract surgery?

To assess variation in reported use of preoperative medical tests in patients undergoing cataract surgery and to identify factors that influence test use by different physician groups we performed a national survey of ophthalmologists, anesthesiologists, and internists. Participants included randomly selected members of American professional societies who provided care to one or more patients undergoing cataract surgery in 1991. Responses were obtained from 538 (82%) of 655 eligible ophthalmologists, 109 (76%) of 143 anesthesiologists, and 54 (44%) of 122 internists. Fifty percent of ophthalmologists, 40% of internists, and 33% of anesthesiologists frequently or always obtained a chest x-ray film, while 20% of ophthalmologists, 27% of internists, and 37% of anesthesiologists never obtained a chest x-ray film for patients being considered for cataract surgery who had no history of major medical problems (P < .01 for differences between ophthalmologists and the other groups). Similarly, 70% to 90% of ophthalmologists, 73% to 79% of internists, and 41% to 79% of anesthesiologists frequently or always obtained a complete blood cell count, electrolyte panel, and electrocardiogram, while 4% to 11% of ophthalmologists, 13% to 17% of internists, and 9% to 28% of anesthesiologists never obtained these tests for such patients. Many respondents (32% to 80%) believed tests were unnecessary but cited multiple reasons for obtaining tests (eg, medicolegal concerns and institutional requirements). Many physicians in each group viewed preoperative evaluations as screening opportunities or believed that one of the other two types of physicians "required" tests. We conclude that marked variation exists within and across physician specialties in the use and rationale for use of medical tests in patients undergoing cataract surgery.

Anesthesiology↗

PubMed1995

Preoperative functional expectations and postoperative outcomes among patients undergoing first eye cataract surgery.

OBJECTIVE: To describe the relationship between patients' preoperative expectations regarding the outcome of cataract surgery and actual postoperative experience. METHODS: A longitudinal study of 772 patients undergoing first eye cataract surgery recruited from 75 ophthalmology practices in three metropolitan areas was conducted. Prior to surgery and approximately 4 months after surgery, a detailed interview was conducted that included general and vision-specific health status measures (including the Visual Function 12-Item Scale [VF-12]), patient-reported level of trouble and satisfaction with vision, and questions addressing patients' preoperative expectations regarding the outcomes of surgery. In addition, detailed clinical data were collected preoperatively and postoperatively. A total of 552 patients had only single eye cataract surgery by 4 months postoperatively and are included in this analysis. RESULTS: Patients' preoperative expectations regarding the impact of cataract surgery were very high and were unrelated to their demographic or ocular characteristics. The preoperative VF-12 score, however, was positively correlated with expected postoperative VF-12 score (Spearman correlation, .45, P < .001). Only 61% of patients achieved or surpassed their expected level of postoperative functioning. The difference between expected and actual postoperative VF-12 scores was not associated with patients' demographic characteristics or provider-related variables. Older patients (> 75 years) and patients with ocular comorbidity had a larger difference between expected and actual postoperative functioning than younger patients and those without ocular comorbidity. CONCLUSION: Expectations regarding visual functioning after cataract surgery are very high, and in most cases such expectations are fulfilled. In selected cases, more comprehensive counseling may reduce the discrepancy between expectations and actual outcomes of cataract surgery.

Aged↗

PubMed1995

Reproducibility and responsiveness of the VF-14. An index of functional impairment in patients with cataracts.

OBJECTIVES: To assess the test-retest reliability and responsiveness of the VF-14, which is an index of functional impairment in patient with cataracts. DESIGN: Observational longitudinal study. Patients were enrolled prior to undergoing their first cataract surgery between July 15 and December 15, 1991, and they were followed up for 1 year after surgery. SETTING: Patients were recruited from 72 ophthalmologists' practices in three US cities. PATIENTS: Five hundred fifty-two patients who had undergone a surgical procedure in only one eye by the 4-month postoperative follow-up (responsiveness analyses) and a subset of these (n = 426) who had not subsequently undergone surgery for the second eye by the 12-month postoperative follow-up (reproducibility analyses). MAIN OUTCOME MEASURES: Two health status measures (the VF-14 and the Sickness Impact Profile, two global measures of a patient's trouble and satisfaction with his or her vision, and best corrected visual acuity in each eye. RESULTS: The VF-14 is highly reproducible, with an intraclass correlation coefficient of .79 when patient-rated criteria are used to define stable patients. The intraclass correlation coefficient was lower (.57 to .71) when various measures of visual acuity were used to define stable patients. The VF-14 is also about three times more responsive to a change in vision than the Sickness Impact Profile, which is a generic health status measure (effect size of approximately 1.00 vs 0.30). Estimates of the responsiveness of the VF-14 and the Sickness Impact Profile were not associated with preoperative visual acuity in the operated on or better eye. Responsiveness of the VF-14, however, was higher in patients with greater self-rated trouble with vision preoperatively. CONCLUSIONS: The VF-14 was reproducible in stable patients during an 8-month period, and it was more responsive to clinically significant changes in vision than was a generic health status measure (ie, the Sickness Impact Profile).

Aged↗

PubMed1995

Comparison of generic versus disease-specific measures of functional impairment in patients with cataract.

The increased demand for health status measures in evaluating medical interventions has increased the importance of clarifying when to use generic versus disease-specific health status measures. The authors compared the performance of a well known generic health status measure, the Sickness Impact Profile (SIP), and a disease-specific measure of functional impairment related to vision (the VF-14) in detecting functional impairment in 426 cataract patients before and at 12 months after first eye cataract surgery. Using analysis of covariance models, the associations were assessed between the SIP and VF-14 and four criterion variables--patient ratings of trouble and satisfaction with their vision and overall health, and best corrected visual acuity--after controlling for patient age and medical comorbidities. Preoperative patient ratings of trouble and satisfaction with vision were significantly associated with VF-14 scores (P < 0.001), but not with SIP scores. Preoperative visual acuity in the better eye was significantly associated with both VF-14 and SIP scores (P < 0.001). Patient general health ratings were significantly associated with SIP scores (P < 0.001), but not with VF-14 scores. Postoperative changes in patient ratings of their vision and in visual acuity were significantly associated with changes in VF-14 scores (P < 0.05), but not with changes in SIP scores. Changes in patient ratings of overall health were significantly associated with changes in SIP scores (P < 0.01), but not with changes in VF-14 scores. In patients undergoing cataract surgery, a disease-specific health status measure is more sensitive to preoperative functional impairment related to vision, and to change in functional impairment after cataract surgery, than is a generic health status measure.

Activities of Daily Living↗

PubMed1994

Internists' attitudes about clinical practice guidelines.

OBJECTIVE: To assess internists' familiarity with, confidence in, and attitudes about practice guidelines issued by various organizations. DESIGN: Cross-sectional, self-administered survey. PARTICIPANTS: Questionnaires were mailed to a stratified random sample of 2600 members of the American College of Physicians (ACP) in 1992. Of the 2513 internists who met our eligibility criteria, 1513 responded (60%). MEASUREMENTS AND RESULTS: Familiarity with guidelines varied from 11% of responders for the ACP guideline on exercise treadmill testing to 59% of responders for the National Cholesterol Education Program guideline. Confidence was reported in ACP guidelines by 82% of responders but by only 6% for Blue Cross and Blue Shield guidelines. Subspecialists had greatest confidence in guidelines developed by their own subspecialty organizations. It was thought that guidelines would improve the quality of health care by 70% of responders, increase health care costs by 43%, be used to discipline physicians by 68%, and make practice less satisfying by 34%. More favorable attitudes were held by internists who were paid a fixed salary, saw patients for less than 20 hours per week, had recently graduated from medical school, or were not in private practice. CONCLUSIONS: Although most ACP members studied recognized the potential benefits of practice guidelines, many were concerned about possible effects on clinical autonomy, health care costs, and satisfaction with clinical practice.

Attitude of Health Personnel↗

PubMed1994

Surgical rates and operative mortality for open and laparoscopic cholecystectomy in Maryland.

BACKGROUND: Since 1989, laparoscopic cholecystectomy has been widely adopted as a treatment for gallstone disease. We analyzed the association between the introduction of this procedure and three variables: the rate at which cholecystectomy was performed in Maryland, the characteristics of patients undergoing cholecystectomy in routine clinical practice, and operative mortality. METHODS AND RESULTS: We used 1985-1992 hospital-discharge data from all 54 acute care hospitals in Maryland, to identify open and laparoscopic cholecystectomies, characteristics of patients undergoing these procedures, and deaths occurring during hospitalizations in which these procedures were performed. The annual rate of cholecystectomy, adjusted for age, rose from 1.69 per 1000 state residents in 1987-1989 to 2.17 per 1000 residents in 1992, an increase of 28 percent (P < 0.001). As compared with patients undergoing open cholecystectomy, patients undergoing laparoscopic cholecystectomy tended to be younger, less likely to have acute cholecystitis or a common-duct stone, and more likely to be white and have private health insurance or belong to a health maintenance organization (P < 0.001). Although the operative mortality associated with laparoscopic cholecystectomy was less than that with open cholecystectomy (adjusted odds ratio, 0.22; 95 percent confidence interval, 0.13 to 0.37) and the overall mortality rate for all cholecystectomies declined from 0.84 percent in 1989 to 0.56 percent in 1992, there was no significant change in the total number of cholecystectomy-related operative deaths because of the increase in the cholecystectomy rate. CONCLUSIONS: In Maryland, although the adoption of laparoscopic cholecystectomy has been accompanied by a 33 percent decrease in overall operative mortality per procedure, the total number of cholecystectomy-related deaths has not fallen because of a 28 percent increase in the total rate of cholecystectomy.

Algorithms↗

PubMed1994

The VF-14. An index of functional impairment in patients with cataract.

OBJECTIVE: To describe the development and the performance of a brief questionnaire designed to measure functional impairment caused by cataract (the VF-14). DESIGN: Observational cross-sectional study. Patients were recruited between July 15 and December 15, 1991. SETTING: Patients were recruited from the practices of 70 ophthalmologists, located in Columbus, Ohio (N = 21), St Louis, Mo (N = 26), and Houston, Tex (N = 23). PATIENTS: Seven hundred sixty-six patients undergoing cataract surgery for the first time. MAIN OUTCOME MEASURES: Preoperative best corrected visual acuity in each eye; scores on the VF-14, a new index of functional impairment in patients with cataract; patient reports of overall trouble and satisfaction with their vision; and scores on the Sickness Impact Profile, a measure of general health status. RESULTS: The VF-14 has high internal consistency (Cronbach's alpha = .85) and correlates more strongly with the overall self-rating of the amount of trouble and satisfaction patients have with their vision than do several measures of visual acuity or the Sickness Impact Profile score. The VF-14 score is moderately correlated with visual acuity in the better eye. CONCLUSIONS: The VF-14 is a reliable and valid measure of functional impairment caused by cataract and provides information not conveyed by visual acuity or a general measure of health status.

Cataract↗

PubMed1994

Variation in ophthalmic testing before cataract surgery. Results of a national survey of ophthalmologists.

Little information is available either for the clinical value of many ophthalmic tests performed preoperatively in the evaluation of patients for cataract surgery or for variation in ophthalmologists' use of such tests. To assess variation in ophthalmologists' use of ophthalmic tests, we conducted a national survey of American Academy of Ophthalmology members. Thirty-three percent, 17%, 37%, and 19% of the respondents reported that they "frequently" or "always" perform glare testing, contrast sensitivity testing, potential acuity measurement, and specular microscopy, respectively, in patients being considered for cataract surgery who have no history of eye disease other than cataract. In contrast, 27%, 54%, 24%, and 48% of respondents reported that they never perform each of these four tests in such patients. Two ophthalmologist characteristics--a surgical volume of greater than 200 cataract extractions per year and performance of surgery in an ambulatory surgical center or private office (as opposed to a hospital)--were independently associated with an increased probability of performing each of these four tests frequently or always. Ten percent or less of the respondents reported that they frequently or always perform electroretinography, visual evoked response testing, photography of fundus or anterior segment, B-scan ultrasonography, formal color vision testing, and formal visual field testing in such patients. Thus, there is considerable variation in ophthalmologists' use of glare testing, contrast sensitivity testing, potential acuity measurement, and specular microscopy. A small percentage of ophthalmologists may be overusing several other tests in the evaluation of patients being considered for cataract surgery.

Adult↗

PubMed1994

National study of cataract surgery outcomes. Variation in 4-month postoperative outcomes as reflected in multiple outcome measures.

BACKGROUND: Although ophthalmologists have long recognized that visual acuity alone is an inadequate measure of visual impairment, the need for and outcomes of cataract surgery historically have been assessed in terms of visual acuity. PURPOSE: To examine the relation among different cataract surgery outcome measures, including a 14-item instrument designed to measure functional impairment caused by cataract (the VF-14), at 4 months after cataract surgery. METHODS: The authors performed a longitudinal study of 552 patients undergoing first eye cataract surgery by 1 of 75 ophthalmologists practicing in Columbus, Ohio, St. Louis, Missouri, or Houston, Texas. Patients were interviewed, and clinical data were obtained preoperatively (July 15, 1991-March 14, 1992) and 4 months postoperatively. RESULTS: The percentage of patients judged to be improved at 4 months after cataract surgery varied by the outcome measure used: Snellen visual acuity (96%); VF-14 score (89%); satisfaction with vision (85%); self-reported trouble with vision (80%); and Sickness Impact Profile score (67%). The change in patients' ratings of their trouble with vision and their satisfaction with vision were correlated more strongly with the change in VF-14 score than with the change in visual acuity (operated eye or better eye). The average change in VF-14 score was unrelated to the preoperative visual acuity in the eye undergoing surgery. CONCLUSION: Estimates of the proportion of patients benefiting from cataract surgery vary with the outcome measure used to measure benefit. Change in VF-14 score, a measure of functional impairment related to vision, may be a better measure of the benefit of cataract surgery than change in visual acuity.

Aged↗

PubMed1993

Variation in utilization of procedures for treatment of peripheral arterial disease. A look at patient characteristics.

OBJECTIVE: To examine associations between demographic characteristics and use of interventional procedures in patients with peripheral arterial disease. DESIGN: Case series drawn from a statewide hospital discharge database. SETTING: Nonfederal acute-care hospitals in Maryland. PATIENTS AND INTERVENTIONS: A total of 7080 cases of angioplasty, bypass surgery, or amputation for lower-extremity peripheral arterial disease in 1988 through 1989. MAIN OUTCOME MEASURE: Use of angioplasty, bypass surgery, and lower-extremity amputation. RESULTS: A total of 1185 angioplasties, 4005 bypass operations, and 1890 amputations were identified. Population-based annual rates showed that angioplasty use peaked at about 70 per 100,000 at the age of 65 to 74 years, bypass surgery use peaked at more than 250 per 100,000 at 75 to 84 years of age, and amputation use peaked at about 225 per 100,000 at 85 years of age and older. The age-adjusted likelihood of having a procedure for peripheral arterial disease was 1.7 times higher in men than in women and 1.6 times higher in blacks than in whites. Compared with patients who had angioplasty or bypass surgery, patients who had amputations were more likely to be more than 65 years old, to be black (odds ratio, 2.5), to have Medicaid or no insurance (odds ratio, 1.7), to have diabetes mellitus (odds ratio, 3.0), and not to have hypertension (odds ratio, 3.1). Compared with patients who had bypass surgery, patients who had angioplasty were more likely to be under 65 years old, to be white (odds ratio, 1.7), and not to have diabetes mellitus (odds ratio, 1.3). CONCLUSION: Patient race is associated with differences in the frequency with which angioplasty, bypass surgery, and amputation are performed for peripheral arterial disease, and insurance status is associated with the likelihood of having amputation.

Black or African American↗

PubMed1993

The content and cost of cataract surgery.

Although more than 1 million cataract surgeries are performed annually in the United States, little is known about the frequency of use or cost of various services provided in connection with this procedure. To assess the frequency with which various ophthalmic, optometric, anesthesia, and medical services are provided in conjunction with cataract surgery and to estimate the cost to Medicare associated with those services, we analyzed 1985 through 1988 Medicare claims records of a nationally representative 5% sample of Medicare beneficiaries. The experience of 57,103 Medicare beneficiaries who underwent extracapsular cataract surgery in 1986 or 1987 that was not combined with another ophthalmologic procedure formed the basis of our analysis. Projections for current costs were performed using 1991 charges allowed by Medicare for physician services. We estimate that the median charge allowed by Medicare for a "typical" episode of cataract surgery in 1991 was approximately $2500. In addition to the $3.4 billion that Medicare spent in 1991 on such "typical" episodes, Medicare spent more than $39 million on miscellaneous "atypical" preoperative ophthalmologic tests, such as specular microscopy (14% of cases) and potential acuity testing (8% of cases), more than $7 million on postoperative ophthalmologic diagnostic tests, such as fluorescein angiography (3% of cases), and more than $18 million on perioperative medical services (most commonly electrocardiography and chest roentgenography). The major determinants of the cost to Medicare associated with cataract surgery are the rate of performance of cataract surgery and neodymium-YAG laser capsulotomy and the charges allowed for these procedures.(ABSTRACT TRUNCATED AT 250 WORDS)

Cataract Extraction↗

PubMed1993

Cost-effectiveness of laparoscopic cholecystectomy versus open cholecystectomy.

To assess the cost-effectiveness of laparoscopic cholecystectomy versus open cholecystectomy from the payer's perspective, we estimated the probabilities of potential outcomes of each procedure, associated quality-of-life effects, and related direct medical charges and incorporated these estimates into a computerized simulation model. The model projects that laparoscopic cholecystectomy will be more effective than open surgery in terms of total mortality and quality-adjusted survival, for both sexes and all ages. Projected 5-year cumulative charges are lower for laparoscopic cholecystectomy than for open cholecystectomy ($5,354 versus $5,525 for 45-year-old women; $6,036 versus $6,830 for 45-year-old men), and the differences increase substantially with increasing age. We concluded that laparoscopic cholecystectomy is likely to be less costly and more effective than open cholecystectomy for most patients, as long as it does not routinely require preoperative cholangiography and is not associated with increased professional fees or increased risks of retained stones or bile duct injury.

Adult↗

PubMed1993

Cost effectiveness of laparoscopic surgery: from whose perspective?

Explore the source record for details and available documents.

Cost-Benefit Analysis↗

PubMed1993

Interventional management of peripheral vascular disease: what did we learn in Maryland and where do we go from here?

Explore the source record for details and available documents.

Algorithms↗

PubMed1993

Cost implications to Medicare of recombinant erythropoietin therapy for the anemia of end-stage renal disease.

The purpose of this study was to estimate the net cost effect to Medicare of the increasing use of recombinant human erythropoietin (EPO) instead of red blood cell transfusions or androgens in the management of anemia for the approximately 100,000 hemodialysis patients in the U.S. End-Stage Renal Disease (ESRD) program. A computerized decision model that takes into account the effectiveness and possible side effects of transfusions, androgens, and EPO and predicts 1- and 5-yr direct medical costs to Medicare associated with each therapy was constructed. Probability estimates for clinical events were derived from the literature. Costs were assigned by use of the amounts Medicare pays providers of ESRD care for: (1) use of EPO, transfusions, and androgens; and (2) health care services related to the treatment of anemia (including complications of treatment and possible reductions in morbidity). For every 10,000 hemodialysis patients treated with EPO, net Medicare expenditures will be much greater than if only transfusions are used by $42,530,000 at 1 yr (6% of ESRD program costs) and by $118,050,000 at 5 yr and also much greater than if androgens are used (by $42,700,000 at 1 yr and $118,370,000 at 5 yr). The increase in cost was highly sensitive to the dose of EPO; moderately sensitive to changes in estimated anemia response rates for EPO, frequency of EPO-induced vascular access clotting, and reduction in cardiovascular or overall morbidity; and slightly sensitive to transfusion rates, estimated anemia response rates for androgens, frequency of EPO-induced seizure or hypertensive complications (stroke, myocardial infarction), frequency of transfusion-related viral infection, and frequency of androgen-induced virilization. Considering both effectiveness and side effects of alternative treatments for the anemia of ESRD, it was projected that the increasing use of EPO will markedly increase the cost to Medicare of ESRD medical care.

Androgens↗

PubMed1993

Efficacy of immune globulin in preventing complications of bone marrow transplantation: a meta-analysis.

To assess the efficacy of immune globulin in preventing CMV infection, interstitial pneumonia, GVHD and death after BMT, we reviewed and synthesized data from 12 published studies (with 1282 patients) in which immune globulin was used prophylactically in BMT patients, controls were included and clinical outcomes were assessed. Data synthesis indicates that immune globulin significantly reduces fatal CMV infection (odds ratio (OR) 0.47, 95% confidence interval (CI) 0.23-0.99), CMV pneumonia (OR 0.61, CI 0.42-0.89), non-CMV interstitial pneumonia (OR 0.57, CI 0.35-0.95) and total mortality (OR 0.74, CI 0.55-0.99). The reduction in acute GVHD was not quite significant (OR CI 0.45-1.02). Complications decrease with both hyperimmune and conventional immune globulin. For CMV-negative transplant recipients, immune globulin decreases symptomatic CMV infection (OR 0.55, CI 0.31-0.94) and interstitial pneumonia (OR 0.34, CI 0.15-0.77). For CMV-positive recipients, immune globulin prevents interstitial pneumonia (OR 0.45, CI 0.26-0.80) but not symptomatic CMV infection (CI 0.41-2.80). We conclude that immune globulin is efficacious in preventing major complications of BMT in both CMV-negative and CMV-positive recipients.

Adult↗