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B G Vickrey

Publications and source records attributed to B G Vickrey.

At least 55 records · Page 3Linked to original sources
PubMed1996

Diagnostic reasoning in neurology.

Studies examining physicians' clinical decisions have demonstrated considerable variation in decisions and practices and identified numerous challenges to effective, efficient, and accurate decision making. Although use of the decision aids and tools described in this article may help overcome many of these challenges, greater self-awareness of the diagnostic reasoning process and the factors influencing decisions also should help improve clinical decisions and reduce variation, irrespective of the use of these tools. Continued research into the determinants and nature of the diagnostic reasoning process will provide additional insights that can be used to develop and apply improved decision aids and corrective procedures to overcome persistent problems.

Decision Support Techniques↗
PubMed1996

US neurologists: attitudes on the US health care system.

Because the American Academy of Neurology (AAN) exists to represent the views and needs of neurologists, a mailed survey to a randomly selected sample of 520 US-based, board-certified or board-eligible neurologist members was conducted in early 1995 to determine their attitudes in four key changing areas of the US health care system: (1) provision of neurologic care, (2) neurology workforce, (3) academic research, industry sponsorship, and pharmaceutical issues, and (4) health care delivery systems issues. Frequency distributions of degree of agreement and disagreement with 40 statements regarding issues in these four areas were tabulated for the entire group of 430 respondents (response rate = 83%). Associations between these attitudes and six demographic and practice variables (age, gender, board certification, practice type, degree of managed care, and geographical region) were evaluated in an exploratory analysis. The high response rate to the survey and the similarity in demographic and practice characteristics of respondents to the entire US-based, board-certified or -eligible AAN membership support that the attitudes that were measured are likely to be representative of US neurologists, excluding resident trainees. The survey results show that neurologists are deeply concerned that patients with chronic neurologic disorders are not receiving all the neurologic services they need. Respondent show uncertainty about whether there is a current oversupply of neurologists but generally agree that there are too many neurology residency positions. Neurologists support industry sponsorship of academic medical center research and new drug development. With respect to many of the current mechanisms for health care cost containment, respondents indicate they have little confidence that these strategies are in the best interests of patients or physicians. The survey results confirm that there is no consensus among US neurologists on how to improve today's health care delivery system, and the results suggest that certain attitudes are related to neurologists' demographic and practice characteristics. Since today's health care market is volatile, regular assessments of neurologists' attitudes will be needed to assure that their views are understood and clearly represented by the AAN.

Adult↗
PubMed1995

Outcomes in 248 patients who had diagnostic evaluations for epilepsy surgery.

Surgery for intractable epilepsy is a widely used treatment that is not readily assessed by randomised trials. We evaluated the impact of epilepsy surgery on seizures, medication use, employment, and the quality of life in 248 adults and adolescents consecutively referred to one medical centre between 1974 and 1990. Outcomes were determined through self-administered questionnaire and medical record review for 202 surgery and 46 non-surgery patients whose treatment was usually determined by the presence or absence of an epileptogenic focus. Surgery and non-surgery patients differed at baseline only in median monthly seizure frequency (surgery lower than non-surgery). After adjustment for baseline covariates, surgery patients at follow-up had greater decline in average monthly seizure frequency (-11.9 vs - 1.5; difference -10.4, 95% CI -20.5, -0.3) and took fewer antiepileptic medications (average number 1.4 vs 2.0; difference -0.67, 95% CI -0.94, -0.40). Although quality-of-life scores were higher (p < 0.05) with surgery on 5 of 11 scales that were administered only at follow-up, there were no significant differences in employment status or prospectively assessed quality of life. Relative to a non-surgery group, patients treated surgically had better seizure control with less antiepileptic medication. The impact of epilepsy surgery on quality of life and employment needs to be assessed in larger prospective studies.

Adolescent↗
PubMed1995

The relationship of neuropsychological functioning to quality of life in epilepsy.

OBJECTIVE: To examine the relationship of objectively assessed cognitive functioning to self-reported quality of life. DESIGN: Correlational, multiple regression, and factor analytic comparisons of a new self-report quality of life inventory with neuropsychological tests of cognition and mood. SUBJECTS: Two hundred fifty-seven patients with epilepsy. SETTING: Twenty-five epilepsy centers and neurology clinics across the United States. MEASURES: A recently developed self-report (ie, Quality of Life in Epilepsy-89 inventory) and objective tests of memory, verbal abilities, spatial functions, psychomotor and cognitive processing speed, cognitive flexibility, and mood. RESULTS: Factors that assessed mood, psychomotor speed, verbal memory, and language correlated significantly with selected scales of the Quality of Life in Epilepsy-89 inventory (P < .0001) and were predictive of overall quality of life (P < .002 to P < .0001). The mood factor showed the highest correlations (r = -.20 to r = -.73) and was the strongest predictor of quality of life in regression analyses (46.7% explained variance, P < .0001). CONCLUSIONS: Mood may be adversely affected by diminished quality of life, or perceived quality of life may be affected by mood disturbance. Quantitative quality of life assessments can be used in conjunction with formal neuropsychological testing of mood and cognition when evaluating patients with epilepsy.

Adult↗
PubMed1995

Outcome assessment for epilepsy surgery: the impact of measuring health-related quality of life.

Epilepsy surgery is an increasingly common treatment for intractable epilepsy; yet there is no clear consensus among experts on how to report epilepsy surgery outcome. Most published outcome reporting systems focus on seizure frequency and type but differ in how they define clinically distinct outcome categories. We used a reliable and valid measure of self-reported health-related quality of life (HRQOL), the Epilepsy Surgery Inventory (ESI)-55, as an external standard by which to evaluate seven previously published, seizure-based outcome classification systems. The ESI-55 was administered to 133 adults who had previously undergone surgery for intractable epilepsy, and results were linked to data on their seizure occurrence before and after surgery (over the year prior to their HRQOL reports). These 133 patients were classified according to each seizure-based outcome system, and variation in HRQOL across outcome groups was evaluated using analysis of variance. Results reveal noteworthy variation in the extent to which different systems reflect patients' HRQOL at follow-up. We modified existing systems to derive a seizure-based surgery outcome system that most closely reflects HRQOL when applied over the latest 1-year postoperative interval.

Adolescent↗
PubMed1995

The Q-TWiST approach to assessing health-related quality of life in epilepsy.

We propose to develop a methodology for evaluating clinical interventions for epilepsy in terms of their effects on disease-related outcomes, social cost and quality of life, while incorporating patient preference. The technique represents an extension of the 'quality-adjusted time without symptoms and toxicities' (Q-TWiST) method, which has been previously used to evaluate treatments for cancer and AIDS with respect to their costs in terms of toxicities, and benefits in terms of improved progression-free and overall survival. The extensions we propose to develop allow additional dimensions of quality of life relevant to epilepsy to be included in the analysis. We demonstrate a possible application of the proposed Q-TWiST method with a hypothetical example comparing surgery vs antiepileptic medication management alone for seizure control. The trade-offs between these alternative treatments are highlighted, along with patient importance weightings regarding various dimensions of quality of life. We describe further research needed to develop the methodology fully and comment on its potential usefulness.

Anticonvulsants↗
PubMed1995

Agreement between self reports and proxy reports of quality of life in epilepsy patients.

Agreement between self reports and proxy reports of quality of life was examined in a sample of 292 patients with epilepsy and their designated proxies. Patients and proxies completed an 89-item Quality of Life Inventory (QOLIE-89), with the items rephrased for the proxy. Results reveal moderate correlations (product-moment r ranging from 0.29 to 0.56 for 17 multi-item scales) between self reports and proxy reports. Agreement was good for measures of function that are directly observable and relatively poor for more subjective measures. Mean scale scores were significantly different between patients and proxies for only five of 17 multi-item scales. Proxy respondents systematically reported better functioning than did patients in three scales assessing cognitive functioning (all p < 0.001). By contrast, patients reported more positive health perceptions and less seizure distress than proxies. Patient educational attainment correlated inversely with degree of disagreement between patient and proxy reports for six of the 17 QOL scales and for the overall score. In addition, proxy educational attainment correlated positively with agreement for four scales. This study indicates that for group level comparisons, proxy respondents can be substituted for adults with epilepsy having low to moderate seizure frequency. However, for individual level assessments proxies should be used with caution.

Adolescent↗
PubMed1995

The routine use of health-related quality of life measures in the care of patients with epilepsy: rationale and research agenda.

Reliable and valid patient-completed questionnaires to assess the health related quality of life (HRQOL) of people with epilepsy are becoming increasingly available. At present, however, they are not routinely used in epilepsy patients' care. The use of HRQOL measurement in clinical practice settings may improve the quality of care for people with epilepsy through (1) increasing the detection of patients' problems with daily functioning and well-being: (2) guiding therapeutic management; and (3) leading to improvements in patients' HRQOL and satisfaction with care. To realize the potential benefits of HRQOL assessment in the care of people with epilepsy, research into the feasibility of the office-based use of HRQOL questionnaires, measurement quality, and the impact of routine HRQOL assessment on the quality of epilepsy patients' care needs to be undertaken. The transfer of HRQOL questionnaires from research tools into clinical tools requires the collaboration of social scientists, health services researchers, and clinicians. HRQOL questionnaires have the potential to become a new clinical tool which could enhance the quality of care physicians are able to provide for their patients with epilepsy.

Anticonvulsants↗
PubMed1995

A health-related quality of life measure for multiple sclerosis.

The need for measures of health-related quality of life (HRQOL) for clinical effectiveness research and for quality of care research, particularly for chronic diseases, is increasingly recognized. We assessed a measure of HRQOL for people with multiple sclerosis, a chronic neurological condition. We used the RAND 36-Item Health Survey 1.0 (aka SF-36) as a generic core measure, to enable comparisons of HRQOL of patients with multiple sclerosis to those of other patient populations and to the general population. To enhance comparisons within groups of multiple sclerosis patients, these items were supplemented with 18 additional items in the areas of health distress (four items), sexual function (four items), satisfaction with sexual function (one item), overall quality of life (two items), cognitive function (four items), energy (one item), pain (one item), and social function (one item). The final measure, the Multiple Sclerosis Quality of Life (MSQOL)-54 Instrument, contains 52 items distributed into 12 scales, and two single items. Internal consistency reliability estimates for the 12 multi-item scales ranged from 0.75 to 0.96 in a sample of 179 patients with multiple sclerosis. Test-retest intraclass correlation coefficients ranged from 0.66 to 0.96. Exploratory factor analysis confirmed two underlying dimensions of physical health and mental health. Construct validity was supported by significant associates between MSQOL-54 scales and degree of multiple sclerosis symptom severity in the prior year, level of ambulation, employment limitations due to health, admission to hospital in the previous year, and depressive symptoms.

Activities of Daily Living↗
PubMed1995

The clinical-pathogenic mechanisms of hippocampal neuron loss and surgical outcomes in temporal lobe epilepsy.

A retrospective study was carried out to determine whether a prior cerebral injury or medical illness was associated with hippocampal sclerosis in intractable, surgically treated temporal lobe epilepsy (TLE), or whether there was evidence for progressive hippocampal neuron damage from repeated seizures. Temporal lobe epilepsy patients (n = 162) from one epilepsy centre were retrospectively and blindly catalogued into groups based on the presence or absence of an initial precipitating injury (IPI) and whether, when an IPI was present, it had involved seizures (independent variables). Patients were catalogued into four groups: (i) non-seizure IPIs (Group A; n = 54); (ii) IPIs with a prolonged seizure (Group B; n = 66); (iii) IPIs with repetitive non-prolonged seizures (Group C; n = 20); (iv) or no IPIs and idiopathic TLE (Group D; n = 22). The dependent variables were: the differences in the time course of clinical seizures, and quantified hippocampal neuron counts and seizure outcomes. Statistically significant (ANOVA at least P < 0.05) results showed the following. (i) Patients with IPIs (Groups A, B and C) had hippocampal sclerosis, while those with idiopathic TLE (Group D) showed fewer neuron losses and worse post-resection seizure relief. (ii) Patients with non-seizure IPIs (Group A) were on average older at injury; had a longer latent period; showed less neuron losses in Ammon's horn, CA1 and prosubiculum than seizure associated IPIs (Groups B and/or C). (iii) Initial precipitating injury patients with repetitive non-prolonged seizures (Group C) showed the shortest latent period, earliest age of TLE onset, and less CA2 damage than the other IPI groups. Other findings that were statistically significant by analysis of covariance along with the IPI category included the following. (i) CA1 (P = 0.0097) and prosubiculum (P = 0.0089) neuron losses were greater in patients when their TLE was longer than 22 years. (ii) IPIs after age 4 years were associated with latent periods shorter than 10 years compared with variable and longer latent periods of IPIs before age 4 years (P = 0.0015). These results indicate that in surgically treated TLE, hippocampal sclerosis and good seizure outcomes are associated with IPIs. Most of the hippocampal damage found at surgery and the clinical time course of the habitual TLE are influenced by the pathogenic IPI mechanism. However, some secondary neuron losses were associated with longer TLE seizure histories.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1995

Development of the quality of life in epilepsy inventory.

We developed an instrument to measure health-related quality of life (HRQOL) in epilepsy. A 99-item inventory was constructed from the RAND 36-Item Health Survey (generic core), with 9 additional generic items, 48 epilepsy-targeted items, and 6 other items concerning attitudes toward epilepsy and self-esteem. We administered the 99-item inventory to 304 adults with epilepsy at 25 epilepsy centers. Patients and patient-designated proxies completed the inventory and were retested 1-91 days later. A multitrait scaling analysis of these data led to retention of 86 items distributed in 17 multiitem scales (Cronbach's alpha ranged from 0.78 to 0.92). Factor analysis of the 17 multiitem scales yielded four underlying dimensions of health: an epilepsy-targeted dimension, a cognitive factor, mental health, and physical health. Construct validity was supported by significant patient-proxy correlations for all scales and correlations between neuropsychologic tests and self-reported emotional and cognitive function (all p values < 0.05). There were significant negative correlations between the four factor scores derived from the HRQOL scales and neurotoxicity, systemic toxicity, and health care utilization (except for the correlation between mental health factor and health care utilization; all p values < 0.05). Patients who were seizure-free in the preceding year reported better HRQOL for the overall score, three of the four factor scores, and 8 of the 17 scale scores than did patients with a high frequency of seizures. Relative validity analysis showed that the epilepsy-targeted factor and three of its four component scales were more sensitive to categorization of patients by severity of seizure frequency and type than scales tapping physical health, mental health, or cognitive function. These cross-sectional data support the reliability and validity of this measure of HRQOL in epilepsy. The addition of an epilepsy-targeted supplement to the generic core improved the sensitivity to severity of epilepsy. The 86 items included in the field testing were supplemented by three additional items to form the Quality of Life in Epilepsy (QOLIE-89) inventory.

Adolescent↗
PubMed1994

Traumatic compared to non-traumatic clinical-pathologic associations in temporal lobe epilepsy.

This study determined differences in clinical-pathologic characteristics of intractable temporal lobe epilepsy (TLE) patients whose mechanism of cerebral injury and chronic seizures involved a prior history of cerebral trauma compared to those with non-traumatic initial injuries. TLE patients (n = 120) from a single epilepsy center were retrospectively and blindly catalogued into pathogenic groups (independent variables) based on if there was a significant Birth injury (n = 11) or Cerebral trauma (n = 26). These two 'trauma' categories were compared to TLE patients with non-seizure non-trauma histories (Non-Sz/Non-Trauma; n = 17), or a first Prolonged seizure (n = 66). The four groups were compared for differences in the time course of their clinical injuries and seizures, quantified hippocampal neuron counts, other temporal neocortical pathologies, and seizure outcomes (dependent variables). Between group statistically significant (at least P < 0.05) results showed: (1) In Birth injury, 33% had Ammon's Horn (AH) neuron loss under 50%, 54% had other temporal neocortical pathologies, they showed the most CA4 neuron loss, and the worse seizure outcomes. (2) Cerebral trauma were older when injured, 29% had AH loss under 50%, 50% showed other pathologies, and they had the best seizure outcomes. (3) Non-Sz/Non-Trauma showed the least AH and CA4 neuron losses, only 12% had other temporal pathologies, and they had seizure outcomes that were intermediate. (4) Prolonged seizure showed the youngest age of habitual TLE onsets, the greatest AH, CA1, and prosubiculum neuron loss, only 11% had other temporal pathologies, and their seizure outcomes were excellent. These results indicate that in intractable surgically treated TLE, a history of cerebral trauma or birth injury as the pathogenic mechanism of their seizures show different clinical-pathologic features and seizure outcomes compared to non-trauma patients. This supports the notion that in TLE there are different pathogenic mechanisms associated with different types of initial injuries and that patients will have different responses to surgical therapy.

Birth Injuries↗
PubMed1993

A procedure for developing a quality-of-life measure for epilepsy surgery patients.

In 1990, the NIH Consensus Conference Panel on epilepsy surgery called for the development and use of reliable and valid health-related quality-of-life (HRQOL) measures in epilepsy surgery studies. A HRQOL measure for epilepsy surgery patients has been developed and evaluated. The procedure, which could also be used to develop HRQOL measures for other neurological diseases, entails the following steps: (a) specify desired characteristics of the measure; (b) identify relevant HRQOL areas by reviewing the literature; (c) assemble generic core items and disease-specific supplementary items; (d) pilot test and revise the measure; (e) administer revised measure items to a large sample of epilepsy surgery patients; (f) perform item analysis to evaluate hypothesized item placement within scales; and (g) assess the reliability and validity of the scales. The product of this process, the Epilepsy Surgery Inventory (ESI)-55, is a self-report measure of 11 dimensions of HRQOL. It is brief, comprehensive, and reliable; preliminary evidence supports its validity.

Adaptation, Psychological↗
PubMed1992

Reliability and validity of the Katz Adjustment Scales in an epilepsy sample.

Development of quality of life measures de novo is time-consuming and expensive, and a number of instruments are already available for general use. Reevaluation and refinement of quality of life tools are needed to improve the existing pool of measures. In this study, data from a sample of 328 epilepsy patients were used to revise a measure of social adjustment and emotional status developed in the 1960s, the 127-item form R1 of the Katz Adjustment Scales (KAS-R1). Using a comprehensive item analysis procedure, we increased the number of items used in scoring the KAS-R1 from 76 to 113 and substantially improved the reliability of scales in both the original sample of 328 epilepsy patients and in a second administration to a 'cross-validation' sample of 193 epilepsy patients. Support for the validity of the revised KAS-R1 scoring system was obtained in a known groups analysis of patients who had previously undergone surgery for epilepsy: mean scores were significantly higher (p < 0.05) on 11 out of 14 scales in the revised KAS-R1 for patients who were completely seizure-free compared to patients who were having seizures with loss of consciousness, after adjusting for age, gender, and anticonvulsant medication use.

Adaptation, Psychological↗