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V Goel

Publications and source records attributed to V Goel.

At least 73 records · Page 4Linked to original sources
PubMed1997

The seats of reason? An imaging study of deductive and inductive reasoning.

We carried out a neuroimaging study to test the neurophysiological predictions made by different cognitive models of reasoning. Ten normal volunteers performed deductive and inductive reasoning tasks while their regional cerebral blood flow pattern was recorded using [15O]H2O PET imaging. In the control condition subjects semantically comprehended sets of three sentences. In the deductive reasoning condition subjects determined whether the third sentence was entailed by the first two sentences. In the inductive reasoning condition subjects reported whether the third sentence was plausible given the first two sentences. The deduction condition resulted in activation of the left inferior frontal gyrus (Brodmann areas 45, 47). The induction condition resulted in activation of a large area comprised of the left medial frontal gyrus, the left cingulate gyrus, and the left superior frontal gyrus (Brodmann areas 8, 9, 24, 32). Induction was distinguished from deduction by the involvement of the medial aspect of the left superior frontal gyrus (Brodmann areas 8, 9). These results are consistent with cognitive models of reasoning that postulate different mechanisms for inductive and deductive reasoning and view deduction as a formal rule-based process.

Adult↗
PubMed1997

Patterns of initial management of node-negative breast cancer in two Canadian provinces. British Columbia/Ontario Working Group.

OBJECTIVE: To describe the patterns of initial management of node-negative breast cancer in Ontario and British Columbia and to compare the characteristics of the patients and tumours and of the physicians and hospitals involved in management. DESIGN: Retrospective, population-based, cohort study. PARTICIPANTS: All 942 newly diagnosed cases of node-negative breast cancer in 1991 in British Columbia and a random sample of 938 newly diagnosed cases in Ontario in the same year. OUTCOME MEASURES: Number and proportion of patients with newly diagnosed node-negative breast cancer who received breast-conserving surgery (BCS) or mastectomy and who received radiation therapy after BCS. RESULTS: BCS was used in 413 cases (43.8%) in British Columbia and in 634 cases (67.6%) in Ontario (p < 0.001). After BCS, radiation therapy was received by 378 patients (91.5% of those who had undergone BCS) in British Columbia and 479 patients (75.6% of those who had undergone BCS) in Ontario (p < 0.001). In both provinces, lower patient age, smaller tumour size, a noncentral unifocal tumour, absence of extensive ductal carcinoma in situ and initial surgery by a surgeon with an academic affiliation were associated with greater use of BCS. Lower patient age and larger tumour size were associated with greater use of radiation therapy after BCS in both provinces. CONCLUSION: Patient, tumour and physician factors are associated with the choice of initial management of breast cancer in these two Canadian provinces. However, the differences in management between the two provinces are only partly explained by these factors. Other possible explanations, such as the presence of provincial guidelines, differences in the organization of the health care system or differences in patient preference, require further research.

Age Distribution↗
PubMed1997

Written patient information about triple-marker screening: a randomized, controlled trial.

OBJECTIVE: To investigate to what extent a newly revised educational pamphlet on triple-marker screening improves patient knowledge and to identify subgroups of women who may not benefit from these materials. METHODS: Women in six geographically and demographically diverse Ontario sites were allocated randomly to receive the pamphlet on triple-marker screening or a similar-appearing educational pamphlet on daily activities during pregnancy. The primary outcome measure was the Maternal Serum Screening Knowledge Questionnaire, a previously validated 14-item scale. RESULTS: Baseline demographic, obstetric, and medical factors were comparable in the intervention and control groups, as were measures of previous exposure to triple-marker screening. Knowledge scores were significantly higher among the 133 women receiving the intervention pamphlet than among 64 women who received the control pamphlet (0.89 versus 0.52 on a scale from -2 to +2, P < .001). Subgroups not benefiting from the pamphlet on triple-marker screening were women age 25 and younger and those not speaking English at home. Those who had completed university or postgraduate education had high levels of knowledge with and without the pamphlet. CONCLUSION: Written patient information can contribute in an important way to patient knowledge about triple-marker screening. Providers of antenatal care should be made aware of the value of written patient information as well as the limitations for some subgroups of women. These subgroups are likely to require additional educational materials and resources. It would be appropriate to make these materials available to the general public and pregnant women in their physicians' offices.

Adult↗
PubMed1997

The rise of tamoxifen: temporal and geographical trends of tamoxifen use in Ontario.

PURPOSE: To describe the change in use of tamoxifen over time and across countries in Ontario. METHODS: Data from the Ontario Drug Benefit (ODB) plan, Census Canada, and the Ontario Cancer Registry (OCR) were combined and analysed to determine rates of tamoxifen use for females over 65 for each county and the province overall, by year. Rates were analyzed by repeated measures ANOVA to determine significance of changes over time. Consistency of tamoxifen use across counties was determined by the Spearman rank correlation coefficient, and overall variation between counties was described using three statistical techniques: Chi-square analysis, the extremal quotient (EQ), and the systematic component of variation (SCV). RESULTS: The number of one-month tamoxifen prescriptions per incident case of breast cancer rose significantly from 13.51 in 1985 to 20.54 in 1990 (p < 0.001) and to 34.06 in 1992 (p = 0.001). Viewed differently, the number of women over 65 receiving tamoxifen prescriptions per incident case of breast cancer changed from 1.91 in 1985 to 3.14 in 1990 to 4.54 in 1992. Statistically significant variation in the rate of tamoxifen prescribing was demonstrated between Ontario counties in all three years by Chi Squared analysis (p < 0.0001). Both the EQ and the SCV declined from 1985 to 1990, suggesting more uniform prescribing across the province. Little change in overall variation was seen between 1990 and 1992. All counties over time tended to prescribe generic preparations more often and shifted from 10 mg to 20 mg formulations. CONCLUSIONS: The significant increase in the rate of tamoxifen use and trend towards more uniform prescribing across Ontario between 1985 and 1990 coincided with the publication of two important documents outlining the benefits of tamoxifen in early breast cancer. Despite this trend, variation in tamoxifen use between counties remains. There has been little change in uniformity of prescribing since 1990.

Aged↗
PubMed1997

The association between population-based treatment guidelines and adjuvant therapy for node-negative breast cancer. British Columbia/Ontario Working Group.

This study evaluated the impact of province-wide treatment guidelines on consistency of adjuvant therapy for node-negative breast cancer. A retrospective population-based cohort study was conducted in the Canadian provinces of British Columbia, which has province-wide guidelines, and Ontario, which does not. All eligible 1991 incident cases of node-negative breast cancer in British Columbia (n = 942) and a similar number of randomly selected 1991 incident cases in Ontario (n = 938) were reviewed. Consistency of adjuvant therapy received was evaluated by stratifying cases into discrete diagnostic groups using several grouping systems, and by then comparing the distribution of treatments received within each diagnostic group in the two provinces. Recursive partitioning was also performed. We observed that patterns of pathology reporting were consistent with awareness of the factors used in the British Columbia guidelines to define indications for adjuvant therapy. Consistency of care was greater in British Columbia than in Ontario by all diagnostic grouping systems and by recursive partitioning (P < 0.001), and the observed patterns in British Columbia corresponded to the British Columbia guidelines. We conclude that population-based treatment guidelines can play a role in promoting consistent patterns of adjuvant therapy for women with node-negative breast cancer.

Aged↗
PubMed1997

A study of the performance of patients with frontal lobe lesions in a financial planning task.

It has long been argued that patients with lesions in the prefrontal cortex have difficulties in decision making and problem solving in real-world, ill-structured situations, particularly problem types involving planning and look-ahead components. Recently, several researchers have questioned our ability to capture and characterize these deficits adequately using just the standard neuropsychological test batteries, and have called for tests that reflect real-world task requirements more accurately. We present data from 10 patients with focal lesions to the prefrontal cortex and 10 normal control subjects engaged in a real-world financial planning task. We also introduce a theoretical framework and methodology developed in the cognitive science literature for quantifying and analysing the complex data generated by problem-solving tasks. Our findings indicate that patient performance is impoverished at a global level but not at the local level. Patients have difficulty in organizing and structuring their problem space. Once they begin problem solving, they have difficulty in allocating adequate effort to each problem-solving phase. Patients also have difficulty dealing with the fact that there are no right or wrong answers nor official termination points in real-world planning problems. They also find it problematic to generate their own feedback. They invariably terminate the session before the details are fleshed out and all the goals satisfied. Finally, patients do not take full advantage of the fact that constraints on real-world problems are negotiable. However, it is not necessary to postulate a 'planning' deficit. It is possible to understand the patients' difficulties in real world planning tasks in terms of the following four accepted deficits: inadequate access to 'structured event complexes', difficulty in generalizing from particulars, failure to shift between 'mental sets', and poor judgment regarding adequacy and completeness of a plan.

Brain Diseases↗
PubMed1997

Sore throat management practices of Canadian family physicians.

OBJECTIVES AND METHODS: A survey was conducted of Canadian family physicians about their usual sore throat management practices. Physician knowledge, attitudes, beliefs and the effect of selected patient factors on variation in practices was assessed. RESULTS: The majority of physicians did not follow North American expert recommendations to usually take a throat culture and wait for culture results before prescribing an antibiotic. Similarly to the practices of family physicians in many countries, they favoured a clinical policy of selective use of throat cultures and decisions about the need for antibiotics based on clinical judgement. CONCLUSIONS: Physician practice site, demographics, knowledge, attitudes, beliefs and patient factors did not explain differences in approach. The implications for antibiotic utilization in the management of upper respiratory tract infections are discussed.

Adult↗
PubMed1997

Enthusiasm or uncertainty: small area variations in the use of mammography services in Ontario, Canada.

STUDY OBJECTIVE: To examine the variation in mammography utilisation in relation to age group and indication across health planning regions in Ontario, Canada. DESIGN: This study includes all women aged 30 and over in Ontario who received a mammogram between July 1, 1990 and December 31, 1991. Data from a sample of 10,000 women aged 50-69 were used to assign mammogram indication as "screening", "possible diagnostic", or "probable diagnostic" based on previous health care utilisation patterns. Age specific rates and age adjusted rates in relation to age group (30-39, 40-49, 50-69, and 70 + years) and region were derived. MAIN RESULTS: Overall, 572,762 women received one or more mammograms. Rates increased from 30-54 years and decreased thereafter. Similar variations were seen in the 40-49 and 50-69 age groups. The ranking in the area specific rates remained consistent for all ages except the 30-39 year range. In relation to indication, the largest variation across regions occurred in the screening group. CONCLUSIONS: Mammography utilisation varies across age groups. The greatest variability is for screening, probably because of physician referral patterns, patient uptake, and perhaps access to mammography. The extent of variation was similar when compared between groups where recommendations were consistent (ages 50-59) and where they were inconsistent (ages 40-49) suggesting that perhaps enthusiasm rather than uncertainty is related to regional variation for this procedure.

Adult↗
PubMed1997

Lung capillary changes in hepatic cirrhosis in rats.

The hypoxemia of the hepatopulmonary syndrome may result from dilated intrapulmonary vascular segments. Knowledge of the size, density, and branching frequency of the lung capillaries might confirm this hypothesis and suggest that the pathogenesis may involve vascular dilatation or angiogenesis. To investigate these changes, the common bile duct of rats was tied off to cause biliary cirrhosis. Later (4 wk), the pulmonary vasculature of these animals was cast, and the casts were studied with scanning electron microscopy. In the ligated animals, evidence for enhancement of the bronchial to pulmonary circulation was found: cast vasa vasorum of the pulmonary arteries and cast bronchial veins emptying into pulmonary veins. Ligated animals had more adherent intracapillary cells per alveolus than the sham-operated animals. The diameters of all capillary beds were larger in the ligated animals. The alveolar capillary density was increased, but the branching frequency was not. A few areas suggesting angiogenesis were found. Induction of biliary cirrhosis enhances the pulmonary-systemic circulation, increases intracapillary adherent cells, capillary diameter, and density, and may be associated with angiogenesis.

Animals↗
PubMed1997

Socio-economic status and visits to physicians by adults in Ontario, Canada.

OBJECTIVES: To examine the association between socio-economic status, need for medical care and visits to physicians in a universal health insurance system. METHODS: Cross-sectional analysis of the 1990 Ontario Health Survey, a population-based survey utilizing a multi-stage, randomized cluster sample. The analysis considered only those respondents who were 16 years of age or older from the province of Ontario, Canada: 21,272 males and 24,738 females. RESULTS: There was no difference by education or income in persons having made at least one visit to a general practitioner in the previous year. High income persons were less likely to have made six or more visits to a general practitioner--odds ratio (OR) = 0.67, 95% CI = 0.52, 0.87 for men; OR = 0.66, 95% CI = 0.58, 0.75 for women--but more likely to have made at least one visit to a specialist--OR = 1.42, 95% CI = 1.15, 1.76 for men; OR = 1.25, 95% CI = 1.07, 1.45 for women. A person's need for medical care was the most important determinant of a physician visit. CONCLUSIONS: Self-reported visits to general practitioners in Canada are strongly influenced by a person's need for medical care and are appropriately related to socio-economic status. However, there is a residual association between higher socio-economic levels and greater use of specialist services.

Adolescent↗
PubMed1997

Compliance with practice guidelines for node-negative breast cancer.

PURPOSE: Practice guidelines for cancer management have been in use in the province of British Columbia (BC), Canada, since the mid 1970s. To evaluate practice guideline compliance, treatment received was compared with treatment recommended in a population-based cohort of women with breast cancer. METHODS: All incident cases (n = 939) of invasive, pathologically node-negative breast cancer diagnosed in 1991 were identified from the BC Cancer Registry. Treatment details were abstracted from cancer clinic records for cases referred to the BC Cancer Agency (BCCA) (n = 661) and original source documents for nonreferred cases. Management decisions were considered compliant if the patient received the recommended treatment or was entered onto a randomized trial of the modality being assessed. RESULTS: Overall compliance with adjuvant therapy guidelines was 97% for radiotherapy, 96% for chemotherapy, and 89% for tamoxifen. An oncology specialist was consulted by 94% of patients with an indication for adjuvant treatment and by 58% of those without an indication (odds ratio [OR] = 10.7; 95% confidence interval, 7.0 to 16.4). Compliance with a guideline to deliver radiotherapy was 95%; with chemotherapy, 77%; and with tamoxifen, 68%. Compliance with a guideline that stated no adjuvant treatment was indicated was 99% for radiotherapy, 98% for chemotherapy, and 92% for tamoxifen. Noncompliance among patients with an indication for treatment was related to nonreferral to an oncology specialist and less complete implementation of guideline changes in the community as compared with cancer center practices. CONCLUSION: Compliance was high, but scheduled updating and more effective community implementation could further improve consistency of care.

Aged↗
PubMed1997

Reconsidering sore throats. Part I: Problems with current clinical practice.

OBJECTIVE: To provide evidence-based answers to clinical questions posed by family physicians about Group A streptococcus pharyngitis and to further understanding of why management is controversial. QUALITY OF EVIDENCE: Evidence from randomized trials was not found for most questions. The most critical information came from high-quality community prevalence studies and criterion standard studies of physician clinical judgement. MAIN FINDINGS: Expert recommendations for physician management are not likely to help prevent rheumatic fever, as most people with sore throats do not seek medical care. Current clinical practices result in overuse of antibiotics because accuracy of clinical judgment is limited. CONCLUSIONS: Costs associated with visits for upper respiratory infections as well as increasing antibiotic resistance necessitate reconsidering the current clinical approach. An alternative management strategy is presented in part 2.

Anti-Bacterial Agents↗
PubMed1997

Reconsidering sore throats. Part 2: Alternative approach and practical office tool.

OBJECTIVE: To identify a management approach for Group A streptococcal (GAS) pharyngitis that would address overuse of antibiotics and could be implemented immediately. QUALITY OF EVIDENCE: No randomized, controlled trials were found; four observational studies met our criteria: simplicity, discrimination ability for GAS pharyngitis compared with throat culture, and validation in a different patient population. Only one scoring system fulfilled all three criteria. MAIN FINDINGS: Formal clinical scoring systems have the potential to improve family physicians' ability to identify and manage GAS pharyngitis. One system had been sufficiently validated to support its use in clinical practice. Four clinical characteristics (no cough, fever higher than 38 degrees C, exudate, and tender cervical nodes) linked to explicit management decisions form the basis for a sore throat score. CONCLUSIONS: Use of a clinical score for management of GAS pharyngitis can be recommended on the basis of the rarity of rheumatic fever in modern society, the resources devoted to management of upper respiratory tract illnesses, the volume of antibiotics prescribed, and the emergence of antibiotic resistance as a growing health issue.

Decision Support Techniques↗
PubMed1997

Cholesterol lowering effects of rhubarb stalk fiber in hypercholesterolemic men.

OBJECTIVE: The present study was undertaken to examine the lipid lowering effects of rhubarb fiber prepared by blanching and drying fresh rhubarb stalks. The new fiber source contained 74% dietary fiber, on dry weight basis, with 66% insoluble and 8% soluble fiber. DESIGN: Ten hypercholesterolemic men were assigned to consume 27 g of ground rhubarb stalk fiber per day for 4 weeks. The dietary intake in terms of total energy, lipid and cholesterol was kept unaltered during the study period. Changes in serum lipid profile were monitored by obtaining blood samples before and after the fiber intervention. RESULTS: Rhubarb fiber supplementation resulted in significant lowering of serum total cholesterol (8%) and low-density lipoprotein (LDL) cholesterol (9%), while high-density lipoprotein cholesterol (HDL) concentrations remained unchanged. The depressed total and LDL cholesterol levels returned to baseline after the fiber supplementation was withdrawn for 1 month. CONCLUSION: The rhubarb stalk fiber is effective in lowering serum cholesterol concentrations, especially LDL cholesterol, in hypercholesterolemic men. These results signify the potential use of underutilized rhubarb crop.

Adult↗
PubMed1997

Development of an instrument to measure cancer screening knowledge, attitudes and behaviours.

The development of a comprehensive survey instrument to measure the knowledge, attitudes and behaviours of the general public with regard to cancer screening was the goal of this project. A thorough review of the literature was undertaken, and existing survey instruments were identified and organized according to type of cancer screening behaviour being measured; question foci (predisposing, enabling and reinforcing factors); and survey implementation protocol. A comprehensive survey instrument was developed with the intention that, if feasible, the survey of cancer screening behaviours could be implemented nationally by telephone. Separate survey instruments were developed according to sex. Focus groups were held across Canada to determine the comprehensiveness of the survey items; ease of understanding and ability to respond; feasibility with respect to possible sensitivity of some of the question items; and general implementation issues (e.g. length, sex of interviewer). This paper reports on the qualitative portion of the project. Our study supports the use of qualitative methodology for instrument development and implementation.

Canada↗
PubMed1996

Reducing demand for physician visits through public education: a look at the pilot cold-and-flu campaign in London, Ontario.

OBJECTIVE: To estimate the effect of the Ontario Ministry of Health's pilot public-education campaign launched in London, Ont., on Jan. 15, 1994, to reduce the number of visits to physicians' offices because of cold and flu symptoms. DESIGN: Before-after comparison of claims to the Ontario Health Insurance Plan. OUTCOME MEASURES: Physician billings for visits because of cold and flu symptoms and total billings for all types of visits during the 2 months before and after the start of the campaign, and during the same two periods in the previous year, in London and in the rest of Ontario. RESULTS: By the time the campaign was started, much of the cold and flu season was already over for that winter. Still, the decrease in billings for visits because of cold and flu symptoms in the 2 months after the campaign was introduced was 6% greater in London than in the rest of Ontario. There was virtually no difference in total billings between London and the rest of the province during the same period. CONCLUSION: The modest relative reduction in physician billings for visits because of cold or flu symptoms in London following the introduction of the public-education campaign may have been due to the intervention as well as to other factors.

Accounting↗
PubMed1996

Evaluating patient's knowledge of maternal serum screening.

The objective was to describe the development, characteristics, and initial use of an instrument for assessing knowledge about maternal serum screening (MSS). Items for a knowledge scale were selected based on a review of educational materials, the literature, and expert opinion. Items were pre-tested for comprehensibility and ambiguity in a convenience sample. After extensive pre-testing and pilot testing a 14-item scale, the Maternal Serum Screening Knowledge Questionnaire (MSSKQ) was developed. It was administered to 1084 women attending a maternal registration clinic. The overall knowledge score was compared across socio-demographic groups, and by sources of information about MSS. Mean MSSKQ scores increased with age, education, and family income, and among those reporting having an opportunity to discuss MSS and receiving written material. The MSSKQ is a reliable instrument with good content and construct validity. This tool should be valuable in assessing knowledge and level of informed consent in women receiving MSS and in evaluating the implementation of MSS programmes.

Adult↗