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Results for “Randomized controlled trials”

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At least 379 records · Page 21Linked to original sources

The Oxford Laser Prostate Trial: a double-blind randomized controlled trial of contact vaporization of the prostate against transurethral resection; preliminary results.

OBJECTIVE: To compare the results of contact laser vaporization and transurethral resection of the prostate (TURP) in a double-blind randomized controlled clinical trial. PATIENTS AND METHODS: The study comprised 148 patients with clinical benign prostatic hypertrophy (BPH) who were recruited and allocated randomly to undergo either TURP (72 patients) or laser ablation of the prostate (76 patients). The outcome was assessed using the American Urological Association (AUA -7) symptom score after 1 and 3 months as the primary measure and by urinary flow rates, haematological factors and the duration of hospital stay and length of catheterization. RESULTS: With 90% statistical power, the results at 3 months showed no clinical or statistical difference between the treatments in change in AUA symptom score. A lower blood loss, hospital stay and duration of catheterization significantly favoured the laser treatment, although the failure rate of trial without catheter and the rate of re-operation were higher after laser treatment. CONCLUSIONS: These early data are encouraging for this technique, although the outcome after one year requires evaluation before advocating the widespread uptake of this method.

Aged↗

Is bowel preparation before excretory urography necessary? A prospective, randomized, controlled trial.

PURPOSE: A prospective, randomized, single blind, controlled trial was performed to determine whether routine bowel preparations are necessary for satisfactory visualization of the urinary system during IVP and compare the side effects of several bowel preparation methods. MATERIALS AND METHODS: A total of 200 patients between 17 and 70 years old at the outpatient department who were prescribed IVP were enrolled in this prospective study. Patients were divided into 4 groups and randomly received liquid supper, senna, magnesium sulfate solution and PEG-ELS as bowel preparation before IVP. Control and contrast images were assessed by a radiologist and a urologist blinded to the bowel preparation. IVP was given a visualization score, a fecal residue score, a bowel gas score and an overall quality score. Images were also divided into anatomical sections to assess visualization, and the effect of fecal residue and bowel gas. Questionnaires were prepared about the side effects of bowel preparation. RESULTS: For contrast images there was no significant difference in terms of visualization,, fecal residue, bowel gas and overall quality scores among the 4 groups. The same result was seen on the control image except for fecal residue scores, when the senna and PEG-ELS groups had a lower fecal residue score than the liquid supper group (p = 0.001). Interestingly when considering sectional images, the right renal region of the control image showed that the senna and PEG-ELS groups had better visualization scores with less bowel gas and fecal residue than the liquid supper only group. Patients in all 3 laxative bowel preparation groups except the liquid supper group reported side effects. There was no statistically significant difference among these 3 groups in the attitude toward ingesting laxatives again. CONCLUSIONS: Our results suggest that routine bowel preparation prior to IVP does not improve the visibility or overall quality of control or contrast images, while patients experience certain side effects due to the bowel preparation. The laxative bowel preparation may be helpful only when visualizing the right renal region on the control image.

Adolescent↗

Short-term intravenous milrinone for acute exacerbation of chronic heart failure: a randomized controlled trial.

CONTEXT: Little randomized evidence is available to guide the in-hospital management of patients with an acute exacerbation of chronic heart failure. Although intravenous inotropic therapy usually produces beneficial hemodynamic effects and is labeled for use in the care of such patients, the effect of such therapy on intermediate-term clinical outcomes is uncertain. OBJECTIVE: To prospectively test whether a strategy that includes short-term use of milrinone in addition to standard therapy can improve clinical outcomes of patients hospitalized with an exacerbation of chronic heart failure. DESIGN: Prospective, randomized, double-blind, placebo-controlled trial conducted from July 1997 through November 1999. SETTING: Seventy-eight community and tertiary care hospitals in the United States. PARTICIPANTS: A total of 951 patients admitted with an exacerbation of systolic heart failure not requiring intravenous inotropic support (mean age, 65 years; 92% with baseline New York Heart Association class III or IV; mean left ventricular ejection fraction, 23%). INTERVENTION: Patients were randomly assigned to receive a 48-hour infusion of either milrinone, 0.5 microg/kg per minute initially (n = 477), or saline placebo (n = 472). MAIN OUTCOME MEASURE: Cumulative days of hospitalization for cardiovascular cause within 60 days following randomization. RESULTS: The median number of days hospitalized for cardiovascular causes within 60 days after randomization did not differ significantly between patients given milrinone (6 days) compared with placebo (7 days; P =.71). Sustained hypotension requiring intervention (10.7% vs 3.2%; P<.001) and new atrial arrhythmias (4.6% vs 1.5%; P =.004) occurred more frequently in patients who received milrinone. The milrinone and placebo groups did not differ significantly in in-hospital mortality (3.8% vs 2.3%; P =.19), 60-day mortality (10.3% vs 8.9%; P =.41), or the composite incidence of death or readmission (35.0% vs 35.3%; P =.92) CONCLUSION: These results do not support the routine use of intravenous milrinone as an adjunct to standard therapy in the treatment of patients hospitalized for an exacerbation of chronic heart failure.

Acute Disease↗

Comparison of effects in randomized controlled trials with observational studies in digestive surgery.

OBJECTIVES: To compare the results of randomized controlled trials versus observational studies in meta-analyses of digestive surgical topics. SUMMARY BACKGROUND DATA: While randomized controlled trials have been recognized as providing the highest standard of evidence, claims have been made that observational studies may overestimate treatment benefits. This debate has recently been renewed, particularly with regard to pharmacotherapies. METHODS: The PubMed (1966 to April 2004), EMBASE (1986 to April 2004) and Cochrane databases (Issue 2, 2004) were searched to identify meta-analyses of randomized controlled trials in digestive surgery. Fifty-two outcomes of 18 topics were identified from 276 original articles (96 randomized trials, 180 observational studies) and included in meta-analyses. All available binary data and study characteristics were extracted and combined separately for randomized and observational studies. In each selected digestive surgical topic, summary odds ratios or relative risks from randomized controlled trials were compared with observational studies using an equivalent calculation method. RESULTS: Significant between-study heterogeneity was seen more often among observational studies (5 of 12 topics) than among randomized trials (1 of 9 topics). In 4 of the 16 primary outcomes compared (10 of 52 total outcomes), summary estimates of treatment effects showed significant discrepancies between the two designs. CONCLUSIONS: One fourth of observational studies gave different results than randomized trials, and between-study heterogeneity was more common in observational studies in the field of digestive surgery.

Digestive System Surgical Procedures↗

The AVID trial: evidence based or randomized control trials--is the AVID study too late? Antiarrhythmics Versus Implantable Defibrillators.

A great body of clinical evidence has been accumulated--before and without the AVID trial--showing that implantable defibrillators prolong life better than currently available antiarrhythmic drugs. With this evidence already available, we question the validity of a trial that attempted, in effect, to place a price tag on life and quality of life.

Anti-Arrhythmia Agents↗

Comparison of internal fixation with total hip replacement for displaced femoral neck fractures. Randomized, controlled trial performed at four years.

BACKGROUND: Recent randomized, controlled trials performed at two years postoperatively have shown that a primary total hip replacement is superior to internal fixation for the treatment of a displaced femoral neck fracture in a relatively healthy, mentally competent, elderly patient. The primary aim of the present study was to evaluate the outcomes at four years. METHODS: One hundred and two patients (mean age, eighty years) who had an acute displaced femoral neck fracture were randomly allocated to be treated with total hip replacement or internal fixation. The inclusion criteria were an age of at least seventy years, absence of severe cognitive dysfunction, an independent living status, and the ability to walk independently. The main outcome measurements were hip complications, reoperations, hip function, and health-related quality of life. RESULTS: The mortality rate was 25% in both groups. At the forty-eight-month follow-up evaluation, the rate of hip complications was 4% in the patients treated with total hip replacement and 42% in those treated with internal fixation (p < 0.001) and the reoperation rates were 4% and 47%, respectively (p < 0.001). The arthroplasty group had no additional hip complications or reoperations between the twenty-four and forty-eight-month follow-up visits. In the fixation group, the percentage of hip complications increased from 36% to 42% and the percentage of reoperations increased from 42% to 47% during the same period. The hip function was significantly better and the decline in health-related quality of life was less pronounced in the arthroplasty group than it was in the fixation group at the four, twelve, and twenty-four-month follow-up evaluations. Ninety-seven percent of the patients in the arthroplasty group and 57% of the patients in the fixation group who were available for follow-up at forty-eight months had no hip complications (p < 0.001). CONCLUSIONS: Compared with internal fixation, primary total hip replacement provides a better outcome for mentally competent elderly patients with a displaced femoral neck fracture. The complication and reoperation rates were significantly lower and hip function and health-related quality of life were at least as good at four years after the surgery.

Aged↗

A randomized controlled trial of selective planned delivery.

A prospective randomized controlled trial designed to investigate selective planned delivery is reported: 264 obstetrically normal women in the 38th week of pregnancy were admitted to this trial and 184 completed it. The infants of mothers in the planned delivery group had higher serum bilirubin levels on the fifth day post partum than control infants but no baby required treatment for hyperbilirubinaemia. Mothers in the planned delivery group required significantly greater amounts of pethidine while control mothers had a significantly higher incidence of meconium staining of the amniotic fluid. However, the infants in the two groups had similar Apgar scores at birth. There was one stillbirth in the control group; this was due to unrecognized fetal hypoxia during labour induced at 42 weeks for postmaturity.

Apgar Score↗

Improving cancer pain management in communities: main results from a randomized controlled trial.

The purpose of this randomized controlled community trial is to evaluate the effects of a community intervention utilizing opinion leaders and educational strategies on the cancer pain management knowledge, attitudes, and the practices of physicians and nurses, and cancer pain reported by patients. Six Minnesota communities participated in the study. The three communities randomized to the intervention received educational programs over 15 months. The clinical community opinion leaders participated in a minifellowship, developed community task forces, and interacted with their peers. This strategy was reinforced with community outreach programs, clinical practice guidelines, educational materials, and media events. The primary study end point was patients' pain intensity score. Comparing intervention to control communities, pain prevalence declined slightly, pain management index improved slightly, pain intensity scores increased slightly, patient and family attitude scores did not change, and physicians' and nurses' knowledge and attitude scores improved slightly. None of these changes, however, reached statistical significance. Participation in at least one intervention program improved physicians' and nurses' knowledge and attitude scores that approached statistical significance. Our results suggest that community opinion leaders combined with other educational programs may improve cancer pain management, but this strategy requires further study. The results suggest that more intense intervention application may be effective. Effective strategies to improve cancer pain management remain elusive.

Cohort Studies↗

Patient education and health promotion can be effective in Parkinson's disease: a randomized controlled trial. PROPATH Advisory Board.

We performed a randomized controlled trial to evaluate the effectiveness of a patient education and health promotion program in the treatment of Parkinson's disease. The health promotion program (PROPATH) was designed to improve health confidence, provide information and support, improve physical function through exercise, and work with the physician to optimize medical treatment and compliance. The intervention was delivered by mail, with disease assessment questionnaires completed by patient or caregiver at 0, 2, 4, and 6 months, with computer-generated reports and individualized recommendation letters returned to patients and reports to physicians. Two hundred ninety patients completed the 6-month trial, 140 patients in the intervention group and 150 in a control group of patients who received only questionnaires. The intervention group had significantly increased exercise, decreased "time off" and percentage of time off, reduced side effects, and decreased summary Parkinson's scores by approximately 10% (P > 0.05). Twelve of 13 variables showed differences favoring the intervention group. The rate of progression of summary scores became essentially flat during the program for the intervention group and continued to rise sharply for controls (P > 0.01). Levodopa dose rose for controls and slightly decreased for the intervention group. Doctor visits, hospital days, and sick days were reduced in the intervention group. The quality-of-life assessment demonstrated improvement in patient global, self-efficacy scores, and spouse or caregiver assessments. We conclude that a low-cost patient education program provides a useful adjunct to medical therapy of Parkinson's disease, may reduce costs, and can improve intermediate term outcomes.

Activities of Daily Living↗

A comparison of observational studies and randomized, controlled trials.

BACKGROUND: For many years it has been claimed that observational studies find stronger treatment effects than randomized, controlled trials. We compared the results of observational studies with those of randomized, controlled trials. METHODS: We searched the Abridged Index Medicus and Cochrane data bases to identify observational studies reported between 1985 and 1998 that compared two or more treatments or interventions for the same condition. We then searched the Medline and Cochrane data bases to identify all the randomized, controlled trials and observational studies comparing the same treatments for these conditions. For each treatment, the magnitudes of the effects in the various observational studies were combined by the Mantel-Haenszel or weighted analysis-of-variance procedure and then compared with the combined magnitude of the effects in the randomized, controlled trials that evaluated the same treatment. RESULTS: There were 136 reports about 19 diverse treatments, such as calcium-channel-blocker therapy for coronary artery disease, appendectomy, and interventions for subfertility. In most cases, the estimates of the treatment effects from observational studies and randomized, controlled trials were similar. In only 2 of the 19 analyses of treatment effects did the combined magnitude of the effect in observational studies lie outside the 95 percent confidence interval for the combined magnitude in the randomized, controlled trials. CONCLUSIONS: We found little evidence that estimates of treatment effects in observational studies reported after 1984 are either consistently larger than or qualitatively different from those obtained in randomized, controlled trials.

Bone Density↗

Community health promotion and the randomized controlled trial: approaches to finding common ground.

The randomized controlled trial is the model against which research designs are judged. Concurrent with rising standards of evidence, however, is a trend toward greater inclusiveness in community-based research, exemplified by the Centers for Disease Control and Prevention-funded Prevention Research Centers, a nationwide network of academic-community partnerships engaged in community-based health promotion and disease prevention research. The Yale-Griffin Prevention Research Center developed a replicable process for devising randomized trials in the context of community collaboration. Several examples of trials developed this way and their interim results are provided.

Cardiovascular Diseases↗

Evaluation of cluster randomized controlled trials in sub-Saharan Africa.

Cluster randomized controlled trials (CRCTs) are attractive in settings in which individual randomization is difficult or impossible. This issue is common when studying several health problems in developing countries. The authors aimed to assess empirically the extent to which the prerequisite design and analysis aspects of cluster randomization were taken into account and reported properly in CRCTs conducted in sub-Saharan Africa. CRCTs published in the last three decades were evaluated by using a checklist based on the Consolidated Standards of Reporting Trials (CONSORT) statement. The authors identified 51 eligible CRCTs; 40 of them (78%) had been published after 1990. Only 10 (20%) studies took clustering into account in sample size or power calculations, and only 19 (37%) took clustering into account in the analysis. Intracluster correlation coefficients and design effects were reported in only one (2%) and three (6%) trials, respectively. An increasing number of CRCTs are conducted in sub-Saharan Africa, but many are not analyzed and reported properly. The special features stemming from cluster randomization need to be addressed in the design, analysis, and reporting of these studies.

Africa South of the Sahara↗

Randomized, controlled trials, observational studies, and the hierarchy of research designs.

BACKGROUND: In the hierarchy of research designs, the results of randomized, controlled trials are considered to be evidence of the highest grade, whereas observational studies are viewed as having less validity because they reportedly overestimate treatment effects. We used published meta-analyses to identify randomized clinical trials and observational studies that examined the same clinical topics. We then compared the results of the original reports according to the type of research design. METHODS: A search of the Medline data base for articles published in five major medical journals from 1991 to 1995 identified meta-analyses of randomized, controlled trials and meta-analyses of either cohort or case-control studies that assessed the same intervention. For each of five topics, summary estimates and 95 percent confidence intervals were calculated on the basis of data from the individual randomized, controlled trials and the individual observational studies. RESULTS: For the five clinical topics and 99 reports evaluated, the average results of the observational studies were remarkably similar to those of the randomized, controlled trials. For example, analysis of 13 randomized, controlled trials of the effectiveness of bacille Calmette-Guérin vaccine in preventing active tuberculosis yielded a relative risk of 0.49 (95 percent confidence interval, 0.34 to 0.70) among vaccinated patients, as compared with an odds ratio of 0.50 (95 percent confidence interval, 0.39 to 0.65) from 10 case-control studies. In addition, the range of the point estimates for the effect of vaccination was wider for the randomized, controlled trials (0.20 to 1.56) than for the observational studies (0.17 to 0.84). CONCLUSIONS: The results of well-designed observational studies (with either a cohort or a case-control design) do not systematically overestimate the magnitude of the effects of treatment as compared with those in randomized, controlled trials on the same topic.

Anticholesteremic Agents↗

A double-blinded, placebo-controlled, randomized trial of the neuropsychologic efficacy of cranberry juice in a sample of cognitively intact older adults: pilot study findings.

OBJECTIVES: The aim of this research was to conduct the first known clinical trial of the short-term (i.e., 6 weeks) efficacy of cranberry juice on the neuropsychologic functioning of cognitively intact older adults. PARTICIPANTS: Fifty (50) community-dwelling, cognitively intact volunteers, > or = 60 years old, who reported no history of dementia or significant neurocognitive impairments, participated in this study. DESIGN: A 6-week, double-blind, placebo-controlled, randomized, parallel-group, clinical trial was utilized. Participants were randomly assigned to receive either 32 ounces/day of a beverage containing 27% cranberry juice per volume (n = 25) or placebo (n = 25) for 6 weeks, and administered a series of neuropsychologic tests at both pretreatment baseline and again after 6 weeks of either cranberry juice or placebo treatment to assess treatment-related changes. OUTCOME MEASURES: Efficacy measures consisted of participants' raw scores on the following standardized neuropsychologic tests: Selective Reminding Test, Wechsler Memory Scale-III Faces I and Faces II subtests, Trail Making Test (Parts A and B), Stroop Color and Word Test, and the Wechsler Adult Intelligence Scale- III Digit Symbol-Coding subtest. A subjective Follow-up Self-report Questionnaire was also administered to participants at the conclusion of the end-of-treatment phase assessments. RESULTS: Two-factor, mixed analyses of variance (ANOVA) revealed no significant group (cranberry juice and placebo) by trial (pretreatment baseline and end-of-treatment assessments) interactions across all of the neuropsychologic tests and measures utilized in this study when a Bonferroni corrected alpha level was used to correct for multiple comparisons (i.e., .05/17 group by trial comparisons = .003). Pearson Chi-Square analyses of the groups' self-reported changes over the 6-week treatment phase in their abilities to remember, thinking processes, moods, energy levels, and overall health on the Follow-up Self-report Questionnaire revealed no significant relationships. However, a nonsignificant trend (X2(1) = 2.373, p = 0.123) was noted for participants' self-reported overall abilities to remember from pretreatment baseline to the end-of-treatment assessment. Specifically, more than twice as many participants in the cranberry group (n = 9, 37.5%) rated their overall abilities to remember by treatment end as "improved" as compared to placebo controls (n = 4, 17.4%). CONCLUSIONS: Taken together, no significant interactions were found between the cranberry and placebo groups and their pretreatment baseline and end-of-treatment phase (after 6 weeks) standardized neuropsychologic assessments. A nonsignificant trend was noted, however, on a subjective, self-report questionnaire where twice as many participants in the cranberry group rated their overall abilities to remember by treatment end as "improved" compared to placebo controls.

Aged↗

Defining the standard of care in randomized controlled trials of titrated therapies.

PURPOSE OF REVIEW: To discuss the appropriate standard of care in randomized controlled trials of titrated therapies in critically ill patients. RECENT FINDINGS: The debate over the appropriate standard of care in randomized controlled trials was sparked by the Acute Respiratory Distress Syndrome Network trial of low tidal volume ventilation. In this trial, patients were randomized to either low or traditional tidal volume ventilation, and the investigators reported that low tidal volume ventilation significantly improved survival in patients with acute respiratory distress syndrome. However, it was argued that the control group used in this trial was not reflective of current practice patterns and that the improvement in survival may have been derived from patients in the control group being placed at increased risk. This debate forced intensivists to consider what defines an appropriate standard-of-care control group in randomized controlled trials of titrated therapies. If titrated therapies are to be studied safely, the mechanism behind the titration must be understood and incorporated into the control group. Failure to include a comparator group receiving current practice creates a study design that may jeopardize patient safety because there is no control group representing probable patient outcome outside of the trial. Additionally, randomizing patients to the extremes of a range of care without incorporation of a current practice control group prevents the investigators from making valid recommendations for changing current practice. SUMMARY: The incorporation of current practice patterns into randomized controlled trials of titrated therapies is essential for producing generalizable results and safeguarding patients.

Decision Making↗

How well are randomized controlled trials reported in the dermatology literature?

OBJECTIVE: To assess the methodological quality of the design and reporting of randomized controlled trials published in one major dermatology specialty journal. DESIGN AND DATA SOURCES: In a survey of all published parallel group randomized controlled trials, we found 73 reports with allocation described as randomized from all issues of Clinical and Experimental Dermatology from its inception in 1976 through 1997. MAIN OUTCOME MEASURES: Direct and indirect measures of the adequacy of randomization, trial sample size, baseline comparisons, and intention-to-treat analysis. RESULTS: Hand searching identified 73 randomized controlled trials, but only 31 of these were found by searching MEDLINE for the publication type clinical trials. Of the 73 randomized controlled trials, 68 contained sufficient information to include in the analysis. Only 1 study (1%) reported the method of random sequence generation, and only 5 studies (7%) reported adequate concealment of allocation. Among 38 trials that used simple randomization, the sample sizes in the comparison groups were identical in 22 occasions, raising the possibility that simple randomization might not have been adequately generated or concealed. Most trials (88%) excluded some randomized participants from their analysis. The median sample size was 23 per trial. Only 1 trial reported sample size and statistical power considerations and had an a priori main hypothesis. CONCLUSIONS: Hand searching is important for locating all relevant trials. There is the need for higher methodological quality in clinical trial reporting in dermatology journals. The adoption of the CONSORT (Consolidated Standards of Reporting Trials) statement and checklist for the reporting of trials should enhance the validity of and strengthen the evidence from clinical trials reports.

Data Collection↗

Intrapartum chemoprophylaxis of perinatal group B streptococcal infections: a critical review of randomized controlled trials.

The purpose of this overview was to critically appraise all published randomized, controlled trials evaluating the efficacy of intrapartum chemoprophylaxis in reducing perinatal group B streptococcal infections. The Oxford Database of Perinatal Trials, Medline, Excerpta Medica, and personal files were used for the literature search. By means of present inclusion criteria to select relevant articles, two independent researchers identified nine randomized, controlled trials. Three trials were excluded because of duplicate publication, one because the randomization process was violated, and one because the outcome data were collected retrospectively. The quality of the methods of the four accepted trials was poor, and because of basic flaws meta-analyses of trial results were not performed. Results of three studies showed a statistically significant reduction in neonatal group B streptococcal colonization rates with intrapartum chemoprophylaxis. Although a trend toward a reduction in proved neonatal infection was reported in three studies, each lacked the power to reach statistical significance. Intrapartum chemoprophylaxis to reduce perinatal group B streptococcal infections is not supported by conclusive evidence from well designed and conducted randomized, controlled trials.

Bacteremia↗

Primary prevention of Pneumocystis carinii pneumonia by inhalation of pentamidine. Preliminary results from a placebo-controlled randomized trial. Swiss Group for Clinical Studies on AIDS.

Patients with AIDS but without pneumocystis carinii pneumonia, patients with advanced AIDS-related complex (ARC), and asymptomatic patients with less than 200 CD4-positive lymphocytes/mm3 were randomized to one of two groups: group I: Inhalation of 300 mg of pentamidine every 28 days; group II: Inhalation of placebo (300 mg of Na isethionate) every 28 days. From May to November 28, 1989, 160 patients have entered the trial. Inhalations were well tolerated, with only a 6% use of bronchodilators and a 15% incidence of cough. Until now five patients died, none of them drug related. So far, six patients have developed pneumocystis carinii pneumonia; four of these were on pentamidine, and two on placebo. Five of the six cases occurred before the second inhalation. Recruitment will continue until 250 patients are enrolled.

Administration, Inhalation↗