Showing papers by "Gordon H. Guyatt published in 1993"
TL;DR: Patients, clinicians, and health care administrators are all keenly interested in the effects of medical interventions on HRQL, because increasing efforts exist to incorporate HRQLs as measures of the quality of care and of clinical effectiveness, and because payers are beginning to use HRQL information in reimbursement decisions.
Abstract: Clinicians and policymakers are recognizing the importance of measuring health-related quality of life (HRQL) to inform patient management and policy decisions. Self- or interviewer-administered qu...
3,444 citations
TL;DR: An internal medicine resident in a rheumatology rotation and seeing a 19-year-old woman who has had systemic lupus erythematosus diagnosed on the basis of a characteristic skin rash, arthritis, and renal disease is distressed by the rising creatinine level.
Abstract: CLINICAL SCENARIO You are working as an internal medicine resident in a rheumatology rotation and are seeing a 19-year-old woman who has had systemic lupus erythematosus diagnosed on the basis of a characteristic skin rash, arthritis, and renal disease. A renal biopsy has shown diffuse proliferative nephritis. A year ago her creatinine level was 140 μmol/L, 6 months ago it was 180 μmol/L, and in a blood sample taken a week before this clinic visit, 220 μmol/L. Over the last year she has been taking prednisone, and over the last 6 months, cyclophosphamide, both in appropriate doses. You are distressed by the rising creatinine level and the rheumatology fellow with whom you discuss the problem suggests that you contact the hematology service to consider a trial of plasmapheresis. The fellow states that plasmapheresis is effective in reducing the level of the antibodies responsible for the nephritis and cites a number
915 citations
TL;DR: It is concluded that the Asthma Quality of Life Questionnaire has good measurement properties and that it is valid as both an evaluative and a discriminative instrument and should be considered for inclusion in all asthma studies.
Abstract: The aim of this study was to evaluate the measurement properties of an Asthma Quality of Life Questionnaire. The study design was an 8-wk unblinded single cohort with assessments at 0, 4, and 8 wk. Thirty-nine adults with symptomatic asthma and a wide range of airway responsiveness and medication requirements were enrolled from previous studies and through notices in the local media. Those with inadequately controlled asthma were offered an inhaled steroid (budesonide). Asthma Quality of Life Questionnaire, spirometry, a clinical asthma control questionnaire, medication requirements, airway responsiveness to methacholine, the Sickness Impact Profile, and the Rand questionnaire were recorded at each visit. Patients kept daily diaries of peak flow rates and medications. The Asthma Quality of Life Questionnaire was able to detect changes in patients who responded to treatment or who had natural fluctuations in their asthma (p < 0.001) and to differentiate these patients from those who remained stable (p < 0.001). The Questionnaire was reproducible in patients who were stable (intraclass correlation coefficient = 0.92). There were significant longitudinal and cross-sectional correlations between asthma quality of life and other measures of both clinical asthma and generic quality of life. We conclude that the Asthma Quality of Life Questionnaire has good measurement properties and that it is valid as both an evaluative and a discriminative instrument. It measures the component of asthma most important to patients, and it should be considered for inclusion in all asthma studies.
886 citations
866 citations
TL;DR: A primary care physician inspired by a recent editorial in JAMA about lifelong learning decides to use some of the time he normally takes for continuing medical education conferences for "practice-based education" tailored to his own practice.
Abstract: CLINICAL SCENARIO You are a primary care physician inspired by a recent editorial in JAMA about lifelong learning. 1 You decide to use some of the time you normally take for continuing medical education conferences for "practice-based education" tailored to your own practice. You begin by setting aside 2 hours every week to read about relevant clinical problems. It is now Friday morning and you have 2 hours to spend in the hospital library. You review a one-page list of questions you have generated from the patients you've seen in the prior week. Your questions include these: What should you tell a 33-year-old woman with migraine headaches who has asked for a prescription for sumatriptan after reading a magazine article about it? Should you be screening older men in your practice for prostate cancer? What should you tell the mother of a 6-month-old boy who had a febrile seizure about
645 citations
480 citations
TL;DR: This paper conducted a literature review and a cross-sectional survey to identify the extent to which meta-analyses currently include unpublished data and whether editors, meta-analysts, and methodologists believe unpublished material should be included.
Abstract: Objective. —To identify the extent to which meta-analyses currently include unpublished data and whether editors, meta-analysts, and methodologists believe unpublished material should be included. Design. —This article describes two related studies: a literature review and a cross-sectional survey. Sample Selection. —For the literature review, we identified all articles indexed by the key word meta-analysis from January 1989 to February 1991 and determined whether unpublished material had been searched for, obtained, and included in the meta-analyses. For the cross-sectional survey, we surveyed authors of these meta-analyses, authors of articles addressing methodological issues in metaanalysis published during the same period, and editors of journals in which both types of articles were published. Intervention. —We asked the respondents about their attitudes concerning inclusion of unpublished data and publication of articles from which data had previously been included in a scientific overview. Main Outcome Measures. —Inclusion of unpublished data and opinions about whether unpublished material should be included in overviews and whether prior inclusion of data in an overview should bear on publication. Results. —Of 150 meta-analyses, 46 (30.7%) included unpublished data in their primary analysis. Of authors surveyed, 85% responded. Of the meta-analysts and methodologists, 77.7% felt that unpublished material should definitely or probably be included in scientific overviews; this was true of 46.9% of the editors. A total of 86.4% of the meta-analysts and methodologists and 53.2% of the editors felt that inclusion of data in a prior overview should have no bearing on full publication of original research. Conclusion. —While inclusion of unpublished data in scientific overviews remains controversial, most investigators directly involved in meta-analysis believe that unpublished data should not be systematically excluded. The most valid synthesis of available information will result when meta-analysts subject published and unpublished material to the same rigorous methodological evaluation and present results with and without unpublished sources of data. ( JAMA . 1993;269:2749-2753)
360 citations
TL;DR: To evaluate the effects of osteoporosis on a patient's functional status, direct questioning is required.
Abstract: Objective. To learn about the physical, emotional, and social limitations experienced by postmenopausal women who have back pain due to vertebral fractures resulting from osteoporosis.
Methods. We conducted a cross-sectional survey of female patients with persistent pain due to vertebral fractures.
Results. Respondents had a mean (±SD) bone density of 0.87 ± 0.13 gm/cm2 and a mean (±SD) of 2.48 ± 2.18 fractures. Disability was identified in pain, movement, activities of daily living, and emotion. There was a poor correlation between quality of life and findings on radiography or densitometry.
Conclusion. To evaluate the effects of osteoporosis on a patient's functional status, direct questioning is required.
317 citations
TL;DR: Both generic and specific measures should find increasing use in clinical trials in heart failure, and trials should be constructed to obtain additional data regarding both validity and changes in instrument score that correspond to small, medium and large changes in health-related quality of life.
230 citations
TL;DR: Comprehensive costs and health-related quality of life, measured with the time trade-off preference score, and together with survival data derived from published meta-analyses, cost-utility and cost-effectiveness of early cardiac rehabilitation were estimated.
Abstract: Although there are extensive clinical evaluations of cardiac rehabilitation after acute myocardial infarction (AMI), no full economic evaluation is available. Patients with AMI and mild to moderate anxiety or depression, or both, while still in hospital were randomized to either an 8-week rehabilitation intervention (n = 99) or usual care (n = 102). Comprehensive costs and health-related quality of life, measured with the time trade-off preference score, were obtained in a 12-month trial, and together with survival data derived from published meta-analyses, cost-utility and cost-effectiveness of early cardiac rehabilitation were estimated. The best estimate of the incremental net direct 12-month costs for patients randomized to rehabilitation was $480 (United States, 1991)/patient. During 1-year follow-up, rehabilitation patients had fewer "other rehabilitation visits" (p < 0.0001) and gained 0.052 quality-adjusted life-year more than did the group with usual care. The cost-utility ratio was $9,200/quality-adjusted life-year gained with cardiac rehabilitation during the year of follow-up. This economic evaluation of cardiac rehabilitation does not consider the important distinctions between affordability and worth of alternative health-care services. The data provide evidence that brief cardiac rehabilitation initiated soon after AMI for patients with mild to moderate anxiety or depression, or both, is an efficient use of health-care resources and may be economically justified.
188 citations
TL;DR: Patients with asthma who were symptomatic or required treatment at least once a week, and had airway hyperresponsiveness to methacholine aerosol participated, showed systematically greater HRQL impairment.
TL;DR: An index of scientific quality for health-related news reports and tested its reliability and sensibility, finding the index was found to be sensible with only one major problem, the need for judgment in making ratings.
TL;DR: Thequality of life of subjects with occupational asthma is slightly less satisfactory than that of subjects paired for clinical and functional indices, although the magnitude of the difference is small; and quality of life is weakly correlated with clinical andfunctional indices.
Abstract: Background: The aim of the study was to assess the quality of life in subjects with occupational asthma after removal from exposure to the offending agent by comparison with a group of subjects paired for clinical and functional indices in order to show the separation between the two groups of subjects with a hypothesized different quality of life and relate the impairment in quality of life to anthropometric, clinical, and functional variables. Methods: A previously described asthma quality of life questionnaire (Juniper EF, et al. Thorax 1992; 47:76–83) was administered to two groups of subjects in a prospective manner. Information on the clinical and functional severity of asthma was obtained from each subject. Two groups of subjects were assessed: group 1, 134 subjects with occupational asthma who were seen more than 2 years after the diagnosis was confirmed, and group 2, 91 subjects who were seen in specialized asthma clinics of tertiary care hospitals for treatment of nonoccupational asthma and matched with 91 of the 134 subjects with occupational asthma from group 1 according to need for medication and (when available), baseline forced expiratory volume in 1 second (FEV 1 ) and level of bronchial responsiveness. Results: A statistically significant difference was seen in the four domains (asthma symptoms, limitation of activities, emotional dysfunction, environmental stimuli) and in the total score of the quality of life questionnaire between the two groups of matched subjects; the mean difference in the total score was 0.6 on a scale of 1 (no limitation or none of the time) to 7 (severe limitation or all the time). A weak but statistically significant correlation between the total score and several indices (FEV 1 , bronchial responsiveness and asthma severity) was generally obtained. Conclusion: The quality of life of subjects with occupational asthma is slightly less satisfactory than that of subjects paired for clinical and functional indices, although the magnitude of the difference is small; and quality of life is weakly correlated with clinical and functional indices.
Journal Article•
TL;DR: It is concluded that budesonide taken 400 micrograms daily for 6 weeks was associated with improvements in perennial rhinitis with little evidence of any difference in efficacy or side effects between the powder and aerosol.
Abstract: The aims of the study were to compare the efficacy and side effects of intranasal budesonide as a dry powder and as a freon propelled pressurized aerosol in the treatment of perennial rhinitis and to validate a perennial rhinitis quality of life questionnaire. The design was a single-blind, randomized, parallel group comparison of two active treatments over a 6-week period. Sixty adults with symptomatic perennial rhinitis, stratified for atopy, received 400 micrograms intranasal budesonide administered daily either as one inhalation/nostril/day of pure drug powder or two puffs/nostril/day of drug delivered by a freon propelled aerosol. Subjects kept daily symptom diaries and, at each clinic visit, rhinitis quality of life and adverse experiences were recorded. Fifty-eight subjects completed the study. During the 6 weeks, there were significant improvements in symptoms and quality of life in both treatment groups. The improvements tended to be slightly greater in the aerosol group but the differences did not reach significance. Most frequently reported adverse experiences were headache and nosebleed, which were equally distributed in the two groups. We conclude that budesonide taken 400 micrograms daily for 6 weeks was associated with improvements in perennial rhinitis with little evidence of any difference in efficacy or side effects between the powder and aerosol. The questionnaire is a valid instrument for assessing quality of life in perennial rhinitis clinical trials.
TL;DR: While the GQLQ captures important areas of health-related quality of life impairment for the frail elderly, it failed to show any advantages in either responsiveness or validity to existing, simpler measures.
TL;DR: Most patients can use Beconase AQ as needed successfully for the treatment of hay fever, but there may be an apparently unpredictable minority who do not achieve satisfactory symptom control or quality of life with this approach and who require regular treatment.
Abstract: Background: The objective of this study was to compare regular and "as required" (prn) use of aqueous beclomethasone dipropionate nasal spray (Beconase AQ nasal spray) in the treatment of ragweed pollen-induced rhinitis and to examine possible predictors of unsatisfactory symptom control in the group of patients who used it on a prn basis. Methods: Sixty adults with ragweed pollen-induced rhinitis, who had participated in previous hay fever studies or who responded to media notices, were enrolled in the study. The study design was a randomized, unblinded, parallel group comparison between regular use (400 μg daily) and prn use of Beconase AQ spray during the 6 weeks of the ragweed pollen season. Patients recorded daily symptoms and medication use in diaries. The Rhinoconjunctivitis Quality of Life Questionnaire was administered, and patient satisfaction with symptom control was assessed at clinic visits. Results: Symptoms and quality of life tended to be better in the regular group, but differences were not statistically significant. Twenty-seven percent of patients in the prn group reported unsatisfactory control of symptoms; they experienced significantly worse symptoms and quality of life than the remainder of the prn group and used significantly more Beconase. No obvious predictors of unsatisfactory control were identified. Patients who achieved satisfactory control in the prn group had symptom and quality of life scores that were very similar to those of the regular group. Conclusions: Most patients can use Beconase AQ as needed successfully for the treatment of hay fever, but there may be an apparently unpredictable minority who do not achieve satisfactory symptom control or quality of life with this approach and who require regular treatment.
TL;DR: Relations between the QLMI and other measures provide moderate to strong evidence of its validity in discriminating between patients following AMI according to their health- related quality of life, and in measuring changes in health-related quality oflife over time.
Abstract: The objective of this work was to develop and test a questionnaire to measure health-related quality of life for patients after myocardial infarction (MI). In a cross-sectional survey, 63 patients identified the most frequent and important problems following acute myocardial infarction. The Quality of Life after Myocardial Infarction (QLMI) instrument was developed on the basis of these most frequent and important problems. The QLMI was administered, along with instruments measuring health utilities, social function, and emotional function, in a randomized trial of rehabilitation versus conventional care. The most frequent and important problems fell into areas of symptoms, restriction, confidence, self-esteem, and emotions, each of which is represented in the 26-item QLMI. Effect sizes of the overall QLMI in differentiating between rehabilitation and control groups (0.35), and in detecting improvement over 12 months (1.22) were comparable or larger than any other instrument. The Pearson's correlation coefficient between QLMI administered at 8 and 12 months following AMI varied between 0.75 and 0.87 for the five domains and the overall score. We found substantial correlations of the QLMI with other measures with moderate concordance with predictions about how the instrument should behave if it is a valid measure of health-related quality of life. The QLMI demonstrates a high degree of reliability, and is more responsive than other questionnaires. Relations between the QLMI and other measures provide moderate to strong evidence of its validity in discriminating between patients following AMI according to their health-related quality of life, and in measuring changes in health-related quality of life over time.
Journal Article•
TL;DR: A form was developed to evaluate attending physicians in clinical teaching units according to 14 domains of performance that allowed specification of attending physician behaviour and differentiated areas of strengths and weaknesses between and within attending physicians.
Abstract: With input from faculty members and residents in the internal medicine residency training program at McMaster University, Hamilton, Ont., the authors developed a form to evaluate attending physicians in clinical teaching units according to 14 domains of performance. Although brief, the form included all main areas of teacher performance, allowed specification of attending physician behaviour and differentiated areas of strengths and weaknesses between and within attending physicians. The authors describe the new evaluation process and the results for 41 attending physicians.
TL;DR: Substantial incremental increase in FEV1 in response to increasing doses of beta-agonists beyond those commonly used in clinical practice is restricted to a minority of patients, and lack of reproducibility limits the clinical usefulness of establishing the optimal dose of Beta-agonist for a given patient.
TL;DR: The experience suggests the usefulness of N-of-1 randomized trials in outpatient medical practice, including psychiatric practice, suggests the effectiveness of amitriptyline in psychiatric practice.
Abstract: The objective of this paper is to study the effect of amitriptyline on a young woman with symptoms of lightheadedness, palpitations, somnolence and fatigue. We conducted a single case (N-of-1) randomized trial including three pairs of treatment periods. Each pair included one four-week period when the patient was receiving amitriptyline and one four-week period when the patient was receiving placebo. The clinical setting was a secondary care internal medicine practice. During active treatment periods, amitriptyline was given in a dose of 100 mg each evening. Efficacy symptoms included lightheadedness, headaches and somnolence/fatigue. Side-effects of dry mouth and constipation were also monitored. Each symptom was rated on a seven point scale in which higher numbers denoted fewer symptoms. For the combined efficacy score, the mean difference in scores and the associated standard error was in favour of amitriptyline. The most profound effect was on sleepiness. These differences represent clinically important treatment effects. Dry mouth and constipation were worse on the active drug, but differences did not reach statistical significance. Our experience suggests the usefulness of N-of-1 randomized trials in outpatient medical practice, including psychiatric practice.
TL;DR: A summary of a retreat conducted by the Department of Medicine in which faculty presented and refined strategies they had developed to deal with new challenges for clinical teachers, including incorporating a deeper appreciation of the use of the published literature in day-to-day practice and teaching.
Abstract: New challenges for clinical teachers include incorporating a deeper appreciation of the use of the published literature in day-to-day practice and teaching, responding to the profusion of diagnostic tests and treatments, and dealing with changing practical difficulties. We report a summary of a retreat conducted by our Department of Medicine in which our faculty presented and refined strategies they had developed to deal with these challenges. Areas of discussion include developing an effective medical team managing time on a busy clinical service, teaching pathophysiology, teaching clinical skills, and teaching critical appraisal. Our observations are likely to be useful to clinicians involved in patient-centred teaching in wards and clinics, particularly those interacting with groups of undergraduate and post-graduate trainees.
TL;DR: This scenario focused on the issue of prognosis and concur with Dr Fox's philosophical approach to practice that encourages patient empowerment, and emphasizes one of the important skills that evidence-based teachers must encourage: the careful definition of the question.
Abstract: In Reply. —We thank our correspondents for providing us with the opportunity to reemphasize several key points in our article. Dr Fox has supplied a thoughtful answer to a question that the scenario never asked. While Dr Fox raised the issue of therapy (in which the elements of net costs and benefits and patient utilities are key, as we and others have stressed elsewhere 1 ), our scenario focused on the issue of prognosis. This emphasizes one of the important skills that evidence-based teachers must encourage: the careful definition of the question. We concur with Dr Fox's philosophical approach to practice that encourages patient empowerment. There is evidence to suggest that patients are better if they are empowered, 2 though the matter warrants further study. Since several of the authors of our article previously have identified themselves as nominalists, 1 readers will quickly grasp why we do not accept the narrow,