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At least 163 records · Page 9Linked to original sources
PubMed1995

Failure of orally administered dipyridamole to enhance the antineoplastic activity of fluorouracil in combination with leucovorin in patients with advanced colorectal cancer: a prospective randomized trial.

PURPOSE: A randomized trial was performed to investigate the ability of the nucleoside transport inhibitor dipyridamole (DP) to enhance the antitumor activity of fluorouracil (5-FU)/leucovorin (folinic acid [FA]). PATIENTS AND METHODS: One hundred eighty-one untreated patients with advanced colorectal cancer were randomized to receive 5-FU 600 mg/m2 plus FA 300 mg/m2 on days 2 to 4 with or without DP 75 mg orally three times daily on days 1 to 5. Cycles were repeated every 3 weeks. Only patients with documented tumor progression before therapy were eligible. 5-FU pharmacokinetics using high-performance liquid chromatography (HPLC) were assessed in 11 nonrandomized patients receiving paired cycles with or without DP. RESULTS: One hundred seventy-four patients were assessable for toxicity and response. There was no significant difference in toxicity, except DP-related headache in 24% of patients. An objective response rate of 15% (one complete response [CR] and 13 partial responses [PRs]) for 5-FU/FA and 13% (two CRs and nine PRs) for 5-FU/FA/DP was observed. The dose-intensity of 5-FU delivered was significantly higher (1.09- to 1.16-fold) for the DP-containing arm. Pharmacokinetic parameters of 5-FU did not differ significantly, except for a prolonged half-life (t1/2) induced by DP. The median time to progression (P = .8) and the median survival time (11.6 months for 5-FU/FA v 9.3 months for 5-FU/FA/DP; P = .14, log-rank test) were not different between treatment arms. CONCLUSION: Orally administered DP did not improve the antineoplastic activity of 5-FU/FA in patients with advanced colorectal cancer when used at this dose and schedule. The observed increase in 5-FU dose-intensity for FU/FA/DP was not clinically relevant.

Administration, Oral↗
PubMed1994

Randomized trial comparing weekly versus 3-week chemotherapy in small-cell lung cancer: a Cancer Research Campaign trial.

PURPOSE: A randomized trial of chemotherapy, given on either a 1-week or a 3-week schedule, was performed in small-cell lung cancer (SCLC) patients. The aim was to determine if weekly scheduling produced survival superior to conventional treatment. PATIENTS AND METHODS: Four hundred thirty-eight patients with SCLC with either limited disease (LD; 276 patients) or good-prognosis extensive disease (ED; 162 patients) were randomized. Weekly chemotherapy was 12 alternating cycles of ifosfamide/doxorubicin and cis-platin/etoposide (PE), while 3-week treatment was six alternating cycles of cyclophosphamide/doxorubicin/vincristine (CAV) and PE. Thoracic irradiation was administered 3 weeks after completion of chemotherapy to LD patients who attained a complete response (CR) or partial response (PR). Patients were well matched for clinical characteristics and prognostic factors. RESULTS: Overall response was the same in both arms: 82.3% (39.4% CR) with weekly and 81.1% (36.9% CR) with 3-week treatment. The median survival (MS) durations were 10.8 and 10.6 months for weekly and 3-week chemotherapy, respectively. The 2-year survival rates were 11.8% and 11.7% in the weekly and 3-week arms, respectively. Received dose-intensity (DI) was 73.9% of projected for weekly treatment and 92.7% for 3-week treatment. Hematologic toxicity was the major dose-limiting toxicity for the weekly treatment. CONCLUSION: This trial excludes at 90% power a benefit of greater than 10% for 2-year survival for weekly treatment. The received DI was reduced to a greater extent with weekly treatment, mainly due to hematologic toxicity.

Adult↗
PubMed1994

Comparison of 7 and 8 French guiding catheters for elective PTCA: results of a prospective randomized trial.

A prospective randomized trial was performed to detect technical and clinical differences of 7F compared to 8F guiding catheters (GC) used in elective coronary angioplasty (PTCA). One hundred and fifteen patients undergoing elective PTCA with standard balloon dilatation catheters were randomized to 7F (55 pts) or 8F (58 pts) guiding catheters. The endpoints were primarily coronary artery and peripheral vascular complications; and secondarily, technical details and quantitative and qualitative angiographic quality. There was no difference between 7F or 8F GC for development of coronary or peripheral vascular complications. With 7F GC there was less blood loss (Hct, 3.5 +/- 3.4% vs. 6.5 +/- 9.6%, P = .033), and less contrast medium (160 +/- 88 mL vs. 200 +/- 119 mL, P = .049) used. Angiographic quality was similar, although visualization of lesions in the left anterior descending coronary artery in the left anterior oblique projection was improved with the 8F GC. There is no advantage of 7F GC for the prevention of coronary or peripheral vascular complications, although there was less blood loss and contrast medium used with the 7F systems.

Aged↗
PubMed2006

A randomized trial to assess the impact of opinion leader endorsed evidence summaries on the use of secondary prevention strategies in patients with coronary artery disease: the ESP-CAD trial protocol [NCT00175240].

BACKGROUND: Although numerous therapies have been shown to be beneficial in the prevention of myocardial infarction and/or death in patients with coronary disease, these therapies are under-used and this gap contributes to sub-optimal patient outcomes. To increase the uptake of proven efficacious therapies in patients with coronary disease, we designed a multifaceted quality improvement intervention employing patient-specific reminders delivered at the point-of-care, with one-page treatment guidelines endorsed by local opinion leaders ("Local Opinion Leader Statement"). This trial is designed to evaluate the impact of these Local Opinion Leader Statements on the practices of primary care physicians caring for patients with coronary disease. In order to isolate the effects of the messenger (the local opinion leader) from the message, we will also test an identical quality improvement intervention that is not signed by a local opinion leader ("Unsigned Evidence Statement") in this trial. METHODS: Randomized trial testing three different interventions in patients with coronary disease: (1) usual care versus (2) Local Opinion Leader Statement versus (3) Unsigned Evidence Statement. Patients diagnosed with coronary artery disease after cardiac catheterization (but without acute coronary syndromes) will be randomly allocated to one of the three interventions by cluster randomization (at the level of their primary care physician), if they are not on optimal statin therapy at baseline. The primary outcome is the proportion of patients demonstrating improvement in their statin management in the first six months post-catheterization. Secondary outcomes include examinations of the use of ACE inhibitors, anti-platelet agents, beta-blockers, non-statin lipid lowering drugs, and provision of smoking cessation advice in the first six months post-catheterization in the three treatment arms. Although randomization will be clustered at the level of the primary care physician, the design effect is anticipated to be negligible and the unit of analysis will be the patient. DISCUSSION: If either the Local Opinion Leader Statement or the Unsigned Evidence Statement improves secondary prevention in patients with coronary disease, they can be easily modified and applied in other communities and for other target conditions.

Journal Article↗
PubMed1997

Chemotherapy as an adjunct to radiation in the treatment of squamous cell carcinoma of the head and neck: results of the Yale Mitomycin Randomized Trials.

PURPOSE: Two consecutive randomized trials were run at our institution using the bioreductive alkylating agent mitomycin as an adjunct to radiation therapy in an effort to improve outcome in patients with squamous cell carcinoma of the head and neck. METHODS: Between 1980 and 1992, two consecutive randomized trials using mitomycin (trial 1) and mitomycin with dicumarol (trial 2) as an adjunct to radiation therapy in patients with squamous cell carcinoma of the head and neck were conducted at our institution. The patients were stratified by intent of therapy, extent of disease, and primary tumor site. Within each strata, patients were randomized to receive radiation therapy with or without mitomycin (trial 1) or mitomycin/dicumarol (trial 2). RESULTS: A total of 203 patients were enrolled onto both trials, 195 of whom were eligible for analysis. Patients were equally balanced with respect to sex, age, extent of disease, primary site, radiation dose, and total duration of radiation treatment. Hematologic toxicities were more frequently noted in the drug-treated arms, but were acceptable with no drug-related treatment deaths. Nonhematologic toxicities were acceptable and not significantly different between the two arms. As of September 1995, with a median follow-up of 138 months, a statistically significant benefit occurred in the mitomycin arms with respect to cause-specific survival (0.74 +/- 0.05 v 0.51 +/- 0.05; P = .005), local recurrence-free survival (0.85 +/- 0.04 v 0.66 +/- 0.05; P = .002), and local regional recurrence-free survival (0.76 +/- 0.05 v 0.54 +/- 0.05; P = .003). No statistically significant difference in overall survival was obtained (0.48 +/- 0.05 mitomycin arms v 0.42 +/- 0.05 radiation alone). CONCLUSION: The bioreductive alkylating agent mitomycin is a safe and effective adjunct to radiation therapy in the treatment of squamous cell carcinoma of the head and neck. The statistically and clinically significant improvement in local regional relapse and cause-specific survival obtained support the use of mitomycin as an adjunct to radiation therapy in the management of squamous cell carcinoma of the head and neck.

Adult↗
PubMed2004

Lessons for cluster randomized trials in the twenty-first century: a systematic review of trials in primary care.

BACKGROUND: Evidence suggests that cluster randomized trials are often poorly designed and analysed. There is little recent research on the methodologic quality of cluster randomized trials and none focuses on primary health care where these trials are increasingly common. METHODS: We conducted a systematic review of recent cluster randomized trials in primary health care, searching the Cochrane Controlled Trials Register. We also searched for unpublished trials in conference proceedings, and the UK National Research Register. We assess methodologic quality using a checklist, articulate problems facing investigators conducting these trials, and examine the extent to which carrying out a cluster randomized trial (as opposed to an individually randomized trial) in primary care may reduce power. RESULTS: We found 367 trial reports. Many trials were reported more than once. We characterize 152 independent cluster randomized trials in primary health care published between 1997 and 2000, and briefly describe 47 trials unpublished at December 2000. The quality of design and analysis was variable. Of published trials reporting sample size calculations 20% accounted for clustering in these calculations, 59% of published trials accounted for clustering in analyses. Unpublished trials were more recent and of higher quality. Reporting quality was better in journals reporting more cluster randomized trials. Many trial investigators reported problems with adherence to protocol, recruitment and type of intervention. CONCLUSIONS: Methodologic quality of cluster randomized trials in primary health care is variable and reporting needs improvement. The use of cluster randomization should be indicated in the title or abstract so these kinds of trials are easier to identify. Communicating appropriate methodology to health care researchers continues to be a challenge. Cluster randomized trials should always be piloted and information from pilots and unsuccessful trials shared more widely.

Cluster Analysis↗
PubMed2002

General practitioners' use of magnetic resonance imaging: an open randomized trial comparing telephone and written requests and an open randomized controlled trial of different methods of local guideline dissemination.

AIM: To determine the impact and cost-effectiveness of telephone versus written access to magnetic resonance imaging (MRI), and of different strategies for disseminating locally produced guidelines, upon requests by general practitioners (GPs) for knee and lumbar spine investigation. MATERIAL AND METHODS: Two sequential pragmatic open cluster-randomized trials were conducted within 39 general practices. The outcome measure in each trial was concordance of request with local guidelines. Trial 1: practices requested MRI by telephone or in writing. Trial 2: all practices received guidelines, plus either: a practice-based seminar, practice-specific audit feedback, both seminar and feedback, or neither. RESULTS: A total of 414 requests were assessed in the two trials. Trial 1: telephone access cost pound4.86 more per request but rates of concordant requests were equivalent (65%/64%: telephone/written). Trial 2: compared to the control group, costs per practice were pound1911 higher in seminar group, pound1543 higher in feedback group and pound3578 higher for those receiving both. Concordance was greater following the intervention (74% vs 65%; P < 0.05), but there was no difference between the four study groups. CONCLUSIONS: Method of access did not affect concordance. Written access was more cost-effective. Seminars and feedback were no more effective in modifying practice than guidelines alone, which was thus the most cost-effective option.

Chi-Square Distribution↗
PubMed1999

Conducting randomized trials in general practice: methodological and practical issues.

The evaluation of the outcome of health services technologies is a requirement for their efficient provision in clinical practice. The most reliable evidence for treatment efficacy comes from randomized trials. Randomized trials in general practice pose particular methodological and practical difficulties. In this paper, we discuss how best to plan and manage a clinical trial in this setting. We base our discussion on our experience of conducting randomized trials to evaluate the effectiveness of brief psychotherapy in general practice.

Ethics, Medical↗
PubMed1987

The role of sclerotherapy in the treatment of esophageal varices: personal experience and a review of randomized trials.

Although many more randomized trials will be required to define the role of prophylactic EVS and other therapies (95-99) in the treatment of varices, EVS appears to have a place in the management of varices before they bleed. However, in view of studies recently presented in abstract form (98, 99), it must be stressed that at least in the United States, prophylactic EVS should be restricted to patients in randomized trials. Results from a VA cooperative study (98) led to the conclusion that prophylactic EVS should not be done in male patients with alcoholic cirrhosis and esophageal varices due to excess mortality in the active EVS group (p = 0.009). Although a large number of patients (n = 282) were included into this trial, on the average each of the 12 VA centers treated only 12 patients with EVS. Thus, although investigators were experienced with EVS, a single unforseen problem occurring at each VA center only once could dramatically alter the results of the study. For example, a relatively potent sclerosant solution (45) used in this study may be effective in treating variceal bleeders, but be too toxic and damaging to the esophagus for prophylactic EVS. Also, even though to enter the VA cooperative study, patients were required to have at least three variceal channels, and 89% in the study actually had "large" varices, these "large" varices may not be the same as the "ominous-looking" varices required of the patients in Paquet's study (88, 89, 99). Exactly which subgroups will benefit from each of the various treatments available will be defined as further studies of patients with a high risk of variceal bleeding are completed (95, 99).

Clinical Trials as Topic↗
PubMed2000

Components of variance in a group-randomized trial analysed via a random-coefficients model: the Rapid Early Action for Coronary Treatment (REACT) trial.

Rapid Early Action for Coronary Treatment (REACT) was a multisite trial testing a community intervention to reduce the delay between onset of symptoms of acute myocardial infarction (MI) and patients' arrival at a hospital emergency department. The study employed a group-randomized trial design, with ten communities randomized from within matched pairs to each of two conditions. REACT also employed continuous data collection, based on surveillance of heart attack patients in community emergency departments. They analysed their data by comparing the mean slope for delay time in the ten intervention communities to the mean slope estimated in the ten control communities. Because no estimates of slope variation were available a priori, REACT was sized using approximations based on more traditional designs. In this paper, we present the slope and residual error variances as estimated from the REACT data and examine their influence on the power of the trial post hoc. We also examine the power of the trial as it would have been given a more traditional pretest-post-test design with analysis via a comparison of the net difference in condition means pretest vs post-test.

Ambulances↗
PubMed2001

Reported methodologic quality and discrepancies between large and small randomized trials in meta-analyses.

PURPOSE: To explore whether reported methodologic quality affects estimated intervention effects in randomized trials and contributes to discrepancies between the results of large randomized trials and small randomized trials in meta-analyses. DATA SOURCES: Meta-analyses of randomized trials that included at least one large trial (>/=1000 participants) were included, regardless of the therapeutic area. Eligible meta-analyses were identified through electronic searches and bibliographies of relevant articles. STUDY SELECTION: Full-length randomized trials. DATA EXTRACTION: Methodologic quality was assessed according to reported randomization, double blinding, and follow-up as separate components and by using the Jadad composite scale. DATA SYNTHESIS: Fourteen meta-analyses involving 190 randomized trials from eight therapeutic areas were included. Compared with large trials, intervention effects were exaggerated in small trials with inadequate allocation sequence generation (ratio of odds ratios, 0.46 [95% CI, 0.25 to 0.83]; P = 0.011), inadequate allocation concealment (ratio of odds ratios, 0.49 [CI, 0.27 to 0.86]; P = 0.014), and no double blinding (ratio of odds ratios, 0.52 [CI, 0.28 to 0.96]; P = 0.01). Large trials did not differ significantly from small trials with adequate generation of the allocation sequence, adequate allocation concealment, or adequate double blinding. No association was seen between reported follow-up and intervention effects. The Jadad scale provided no additional information because the scale and the quality components overlapped substantially. CONCLUSIONS: Inadequate generation of the allocation sequence, allocation concealment, and double blinding lead to exaggerated estimates of intervention benefit and may contribute to discrepancies between the results of large randomized trials and small randomized trials in meta-analyses.

Double-Blind Method↗
PubMed2003

Meta-analyses involving cluster randomization trials: a review of published literature in health care.

Throughout the 1980s and 1990s cluster randomization trials have been increasingly used to evaluate effectiveness of health care intervention. Such trials have raised several methodologic challenges in analysis. Meta-analyses involving cluster randomization trials are becoming common in the area of health care intervention. However, as yet there has been no empirical evidence of current practice in the meta-analyses. Thus a review was performed to identify and examine synthesis approaches of meta-analyses involving cluster randomization trials in the published literature. Electronic databases were searched for meta-analyses involving cluster randomization trials from the earliest date available to 2000. Once a meta-analysis was identified, papers on the relevant cluster randomization trials included were also requested. Each of the original papers of cluster randomization trials included was examined for its randomized design and unit, and adjustment for clustering effect in analysis. Each of the selected meta-analyses was then evaluated as to its synthesis concerning clustering effect. In total, 25 eligible meta-analyses were reviewed. Of these, 15 meta-analyses reported simple conventional methods of the fixed-effect model as method of analysis, while six did not incorporate the cluster randomization trial results in the synthesis methods but described the trial results individually. Three meta-analyses attempted to account for the clustering effect in the synthesis methods but approaches were in arbitrary. Fifteen meta-analyses included more than one cluster randomization trial, each of which included cluster randomization trials with a mixture of randomized designs and units, and units of analysis. These mixture situations might increase heterogeneity, but have not been considered in any meta-analysis. Some methods dealing with a binary outcome for some specific situations have been discussed. In conclusion, some difficulties in the quantitative synthesis procedures were found in the meta-analyses involving cluster randomization trials. Recommendations in the applications of approaches to some specific situations in a binary outcome variable have also been provided. There are still, however, several methodologic issues of the meta-analyses involving cluster randomization trials that need to be investigated further.

Cluster Analysis↗
PubMed2003

The compliance score as a regressor in randomized trials.

The compliance score in randomized trials is a measure of the effect of randomization on treatment received. It is in principle a group-level pretreatment variable and so can be used where individual-level measures of treatment received can produce misleading inferences. The interpretation of models with the compliance score as a regressor of interest depends on the link function. Using the identity link can lead to valid inference about the effects of treatment received even in the presence of nonrandom noncompliance; such inference is more problematic for nonlinear links. We illustrate these points with data from two randomized trials.

Bias↗
PubMed1992

Dacron versus polytetrafluoroethylene for Y-aortic bifurcation grafts: a six-year prospective, randomized trial.

BACKGROUND: A prospective, randomized trial was conducted to compare Dacron with expanded polytetrafluoroethylene (ePTFE) in reconstructive aortoiliac surgery. No comparable trial with a prospective, randomized design with a comparable number of patients or an equal long-term follow-up period can be found in the literature. METHODS: Between 1984 and 1989, 165 patients were randomized for either Dacron or ePTFE on the basis of age, sex, indication for surgery, diabetes, nicotine consumption, runoff, and operative approach. The two groups were well matched for randomization criteria, as well as the incidence of aneurysms. RESULTS: No statistically significant difference was found between the two graft materials in terms of patency rates (corrected 3-year patency rates: Dacron = 95% vs ePTFE = 95%; Breslow, p = 0.83; Mantel-Cox, p = 0.74). Subgroup analysis comparing long-term patency rates of the two graft materials and relating them to poor runoff, good runoff, aneurysms, and arterial occlusive disease also failed to show any significant differences between ePTFE and Dacron. Early graft failure (n = 6; 3.6% of the patient population; p = 0.045) and severe abdominal graft infection (n = 3; 1.8% of the total population) were seen only in ePTFE grafts. However, these did not affect the corrected long-term patency rate of ePTFE grafts. There were five late graft failures with PTFE (3.0%) and four with Dacron (2.4%). CONCLUSIONS: Graft materials currently available for aortoiliac repair were comparable in terms of corrected long-term patency rates. The alleged advantages of PTFE were not confirmed by our data. PTFE grafts were associated with a higher rate of complications, and more redo operations were required to duplicate the results obtained with Dacron.

Aorta↗
PubMedDate not supplied

The Consolidated Standards of Reporting Trials (CONSORT): Guidelines for reporting randomized trials.

BACKGROUND: The rules for reporting the results of randomized controlled trials (RCTs) in published manuscripts have been elusive, and many nurse scientists have learned to write research reports by trial and error. APPROACH: New comprehensive guidelines for reporting RCTs are now available to authors, editors, and readers, a development that is likely to improve the quality of published reports. The Consolidated Standards of Reporting Trials (CONSORT) guidelines consist of two parts, a 22-item checklist and a flowchart template, that track the flow of all participants through the RCT. Currently, some journals, including Nursing Research, have adopted CONSORT and suggest or require its use in submitted manuscripts, but other journals do not. RESULTS: The CONSORT has potential to be useful beyond writing manuscripts. Because CONSORT is a comprehensive guide to essential elements of an RCT report, it also provides a useful guide for designing RCTs and writing funding proposals that include all the essential elements of a trial. It also could be a useful synopsis of important concepts when teaching research design to doctoral students. DISCUSSION: Reports of RCTs that use CONSORT are easier to read, interpret, and evaluate for relevancy to clinical practice. In addition, excellent reports of research increase the visibility of nursing research beyond our discipline. The CONSORT adds value to nursing research because researchers and readers alike will benefit if it is used more often.

Nursing Research↗
PubMed1998

The value of the Nd:YAG laser for the surgery of lung metastases in a randomized trial.

OBJECTIVE: A prospective randomized trial was established in our department to compare the usefulness of the neodymium:yttrium-aluminum-garnet (Nd:YAG) laser in resection of lung metastases. We report the results of the first 45 patients after a minimum of 2 years of follow-up. DESIGN: Randomized prospective trial from March 1987 to March 1995. SETTING: University teaching hospital. PATIENTS: Forty-five patients underwent resection for pulmonary metastases with two different techniques chosen at random: 23 patients were treated with an Nd:YAG laser (group A) and 22 patients with a traditional diathermic device (group B). INTERVENTIONS: A total of 71 pulmonary lesions were resected by minimal excision, 41 by laser and 30 by diathermy. Sixty-three lesions were diagnosed as active metastases from various sites. RESULTS: No deaths occurred during surgery. Eight patients (6 in group B) developed minor complications. In two patients from group B, lesions recurred at the resection site. The use of Nd:YAG laser was not associated with a significantly longer survival (log rank test, p=0.49). Laser resection allowed more tissue sparing (mean ratio lesion diameter/volume resected, 0.94 vs 1.11, p<0.008). Univariate and multivariate analyses revealed the importance of laser use in reducing the number of days of postoperative air leakage (3.91 vs 5.00 days) and hospital stay (7.50 vs 9.90 days). CONCLUSIONS: Laser use significantly reduced tissue loss, postoperative air leakage, and hospital stay. Influence on long-term survival was not statistically proven.

Electrocoagulation↗