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Showing papers by "Gordon H. Guyatt published in 1988"


Journal ArticleDOI
19 Aug 1988-JAMA
TL;DR: It is suggested that, for appropriately selected patients, comprehensive cardiac rehabilitation has a beneficial effect on mortality but not on nonfatal recurrent myocardial infarction.
Abstract: Randomized clinical trials of cardiac rehabilitation following myocardial infarction have typically demonstrated a lower mortality in treated patients, but with a statistically significant reduction in only one trial. To overcome the problem of not being able to detect small but clinically important benefits in mortality in randomized clinical trials of exercise and risk factor rehabilitation after myocardial infarction with small numbers of patients, we carried out a meta-analysis on the combined results of ten randomized clinical trials that included 4347 patients (control, 2145 patients; rehabilitation, 2202 patients). The pooled odds ratios of 0.76 (95% confidence intervals, 0.63 to 0.92) for all-cause death and of 0.75 (95% confidence intervals, 0.62 to 0.93) for cardiovascular death were significantly lower in the rehabilitation group than in the control group, with no significant difference for nonfatal recurrent myocardial infarction. These results suggest that, for appropriately selected patients, comprehensive cardiac rehabilitation has a beneficial effect on mortality but not on nonfatal recurrent myocardial infarction. ( JAMA 1988;260:945-950)

1,082 citations


Journal Article
TL;DR: New guidelines that will help readers assess the scientific quality of the review are proposed and will allow clinicians to spend their valuable reading time on high-quality material and to judge the validity of an author's conclusions.
Abstract: One strategy for dealing with the burgeoning medical literature is to rely on reviews of the literature. Although this strategy is efficient, readers may be misled if the review does not meet scientific standards. Therefore, guidelines that will help readers assess the scientific quality of the review are proposed. The guidelines focus on the definition of the question, the comprehensiveness of the search strategy, the methods of choosing and assessing the primary studies, and the methods of combining the results and reaching appropriate conclusions. Application of the guidelines will allow clinicians to spend their valuable reading time on high-quality material and to judge the validity of an author's conclusions.

496 citations


Journal ArticleDOI
TL;DR: It was concluded that oral digoxin, in doses titrated to produce a serum level of 1.54 to 2.56 nmol/liter, improved quality of life and functional exercise capacity in some patients with CHF in sinus rhythm.
Abstract: Because of conflicting results from studies examining the usefulness of digoxin in congestive heart failure (CHF) patients in sinus rhythm, a cross-over trial was conducted in which 20 patients received 7 weeks of digoxin titrated to a level of 1.54 to 2.56 nmol/liter and 7 weeks of matched placebo. The order of treatments was determined by random allocation and patients, clinicians and research staff were blind to allocation. In patients with deteriorating condition, the treatment period was terminated and outcome measures were obtained. If deterioration occurred during the first period, the patient was crossed over without the code being broken. Seven patients required premature termination of study periods because of increasing symptoms of CHF. All 7 were taking placebo at the time (p = 0.016). Small differences in dyspnea (p = 0.044), walking test score (p = 0.055), clinical assessment of CHF (p = 0.036) and ejection fraction (p = 0.004) favored the digoxin treatment group. Patients with more severe CHF were more likely to benefit from digoxin administration. It was concluded that oral digoxin, in doses titrated to produce a serum level of 1.54 to 2.56 nmol/liter, improved quality of life and functional exercise capacity in some patients with CHF in sinus rhythm.

246 citations


Journal Article
TL;DR: The practical approach presented in this paper allows clinicians to conduct their own N of 1 RCTs and suggests formal statistical analysis may be helpful for interpreting the results.
Abstract: In determining optimal treatment for a patient conventional trials of therapy are susceptible to bias. Large-scale randomized trials can provide only a partial guide and have not been or cannot be carried out for most clinical disorders. However, randomized controlled trials (RCTs) in individual patients (N of 1 RCTs) may in some circumstances provide a solution to this dilemma. In an N of 1 RCT a patient undergoes pairs of treatment periods (one period of each pair with the active drug and one with matched placebo, assigned at random); both the patient and the clinician are blind to allocation, and treatment targets are monitored. N of 1 RCTs are useful for chronic, stable conditions for which the proposed treatment, which has a rapid onset of action and ceases to act soon after it is discontinued, has shown promise in an open trial of therapy. The monitoring of treatment targets usually includes quantitative measurement of the patient's symptoms with the use of simple patient diaries or questionnaires. Pairs of treatment periods are continued until effectiveness is proved or refuted. The cooperation of a pharmacy is required for the preparation of matching placebos and conduct of the trial. Formal statistical analysis may be helpful for interpreting the results. The practical approach presented in this paper allows clinicians to conduct their own N of 1 RCTs.

245 citations


Journal ArticleDOI
TL;DR: A comparison of the quality-of-life outcomes of patients in the two treatment groups in the period beyond 3 months after initiation of treatment, revealed that the BCQ and Karnofsky were the only instruments able to demonstrate differences between the groups (P less than .0001).
Abstract: A questionnaire has been developed for use as an outcome measure in clinical trials of adjuvant chemotherapy in women with stage II breast cancer. The selection of items for this Breast Cancer Chemotherapy Questionnaire (BCQ) was based on the problems and experiences felt to be most important by women undergoing adjuvant chemotherapy. The BCQ consists of 30 questions that focus on loss of attractiveness, fatigue, physical symptoms, inconvenience, emotional distress, and feelings of hope and support from others. The BCQ, other instruments that evaluate quality-of-life (Spitzer, Karnofsky, and Rand), and patient and physician global assessments were administered serially to 418 patients taking part in a randomized trial comparing a 12-week regimen and a 36-week regimen of adjuvant chemotherapy. The validity of the BCQ is supported by its correlation with the Rand Emotional (r = .58), Rand Physical (r = .60), and Spitzer (r = .62) questionnaires. The BCQ correlated more strongly with global ratings of both p...

223 citations


Journal ArticleDOI
TL;DR: It is concluded that despite troublesome intestinal and systemic symptoms, most patients with IBD avoid major disruption in work and personal lives and Physicians must inquire specifically about emotional problems relating to IBD.
Abstract: To investigate the effect of inflammatory bowel disease (IBD) on the quality of life, we interviewed 43 patients with ulcerative colitis (UC) and 54 with Crohn's disease. Patients identified frequent and important problems in five areas. Primary bowel symptoms, systemic symptoms, and altered emotional function were common; functional and social impairment were less frequent. Systemic symptoms such as fatigue were more prevalent in patients with Crohn's disease. Apart from primary bowel complaints, patients seldom volunteered other facets of quality of life impairment; this was particularly true for impairment of emotional function. We conclude that despite troublesome intestinal and systemic symptoms, most patients with IBD avoid major disruption in work and personal lives. Physicians must inquire specifically about emotional problems relating to IBD; in particular, fear of surgery is important to address. Psychosocial interventions should be targeted to those patients with problems in this area.

218 citations


Journal ArticleDOI
TL;DR: It is concluded that acute response to inhaled beta agonist is not useful for identifying patients with chronic airflow limitation who are likely to benefit from bronchodilator treatment.
Abstract: • We conducted a four-period cross-over randomized trial in which we found that patients with chronic airflow limitation demonstrated symptomatic improvement with both inhaled albuterol and oral theophylline. The response, however, was not uniform. We therefore tested the ability of acute change in forced expired volume in one second (FEV 1 ) following inhaled beta agonist to predict long-term symptomatic response to albuterol and theophylline. We found that the reproducibility of acute change in FEV 1 over three repetitions was poor (intraclass correlation 0.17). Furthermore, the mean improvement in FEV 1 following inhaled albuterol across the three repetitions did not relate closely to symptomatic response to either albuterol or theophylline. We conclude that acute response to inhaled beta agonist is not useful for identifying patients with chronic airflow limitation who are likely to benefit from bronchodilator treatment. ( Arch Intern Med 1988;148:1949-1952)

80 citations


Journal ArticleDOI
TL;DR: A number of methodologic issues are discussed, such as appropriateness of the patients problem to N of 1 trials, feasibility, types of measurement, as well as timing of these measurements.
Abstract: The N of 1 service at our institution acts as a full referral service for clinicians who want a definitive answer to a difficult management question, and an instructional environment for clinicians who have more time and want to learn to run their own N of 1 RCT. The trial design is a double blind, randomized pair, multiple crossover. A number of methodologic issues are discussed, such as appropriateness of the patients problem to N of 1 trials, feasibility, types of measurement, such as clinical objective measurement and quality of life measurement, as well as timing of these measurements. The analysis issues include developing a reporting method which is statistically powerful and understandable to clinicians with little research background. Some of these issues have been well investigated and some have not.

30 citations


Journal ArticleDOI
TL;DR: The results suggest that an expert cardiological opinion would often be more appropriate than an echocardiogram when the aim is to rule-out disease and on patient anxiety for 300 consecutive referrals.

17 citations