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Results for “Randomized controlled trials”

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PubMed1984

Antibiotic prophylaxis in neurosurgery. A randomized controlled trial.

A randomized trial was performed to support the contention that prophylactic antibiotics can reduce the incidence of postoperative neurosurgical wound infections. The regime outlined by Malis was followed. Vancomycin and gentamicin were administered systemically just prior to surgery and streptomycin was added to the irrigating solution. Patients were randomly assigned to two groups: control and treated. The infection rate in the control group was 3.5% and in the treated group 0.5%.

Adult↗

PubMed1991

A comparison of sucralfate with placebo in the treatment of esophageal ulcers following therapeutic endoscopic sclerotherapy of esophageal varices--a prospective controlled randomized trial.

In 1984 Roark published the first report of a sucralfate treatment of esophageal ulcers after sclerotherapy. Because this was an uncontrolled trial we planned a prospective double-blind placebo-controlled study with 60 patients. After therapeutic paravariceal injection-sclerotherapy of esophageal varices, patients were randomly treated with sucralfate suspension or placebo. Time of treatment was limited to a maximum of 3 weeks and the dosage of sucralfate was 1 g q.i.d. (Ulcogant-Suspension). Healing was assessed by endoscopy at weekly intervals. Fifty-three patients (25 sucralfate, 28 placebo) were evaluable according to the protocol. No patient left the study because of side effects. At the start of the trial, the patients in the sucralfate group showed a larger ulcer area than the placebo group. There was a tendency to faster healing in the sucralfate group, especially in patients with deeper ulcerations. However, there was no significant difference in global healing between both treatment groups after 3 weeks. Sucralfate suspension may be of value in accelerating the healing process in esophageal ulcers after sclerotherapy, especially in patients with deep ulcers. These results should be confirmed in further trials, in which patients should be stratified with respect to their ulcer volume and severity of liver disease.

Aged↗

PubMedDate not supplied

What can randomized controlled trials tell us about nutrition and cancer prevention?

Randomized controlled trials are regarded as the most definitive of study designs. The randomized controlled trials that have tested nutritional factors for cancer prevention are reviewed. Trials that have tested the effects of nutrients given as high-dose supplements have been largely disappointing, typically showing either no or harmful effects. Possible benefits of vitamin E for prostate cancer prevention and selenium for prostate, colorectal, and lung cancer prevention have emerged only as secondary endpoints in trials conducted for other purposes; confirmatory new trials for these nutrients are now underway or are planned. The limitations of both past and current randomized controlled trials for studying diet-cancer relationships are discussed. The disappointing findings that have emerged from short-term studies of high-dose supplements cannot be interpreted as direct tests of the diet-cancer relationship because high-dose supplements cannot fully simulate the effects of whole foods on cancer risk. As we await findings from current and future trials, we should not forget that the ample evidence from observational epidemiologic research--suggesting that diets rich in fruits and vegetables can reduce the risk of many of the most common cancers--can provide a sound basis for nutritional recommendations aimed at reducing cancer risk.

Diet↗

PubMed1994

Review of 39 years of randomized controlled trials in the British Journal of General Practice.

BACKGROUND: Randomized controlled trials are being used increasingly to evaluate the effectiveness of health care interventions, including those in primary care. AIM: A study was undertaken to document the topic areas addressed by randomized controlled trials conducted in primary care and the methodological characteristics of these, based on a historical review of all trials published in the British Journal of General Practice (formerly the Research Newsletter and Journal of the Royal College of General Practitioners) between 1953 and 1991 inclusive. METHOD: Trials were identified by systematically hand searching all back issues. RESULTS: A total of 90 randomized controlled trials were identified, 78% of which were undertaken in general practice. The trials covered a wide range of topics; 62% examined pharmacological interventions, 21% non-pharmacological interventions, and 16% an intervention related to provision of an aspect of health service. Among the randomized controlled trials published there was a significant trend towards more reports on non-pharmacological trials in recent years (P < 0.001). The quality of trials, judged by the extent to which bias was controlled, varied considerably. Trials of pharmacological interventions generally controlled for selection bias at entry and at assessment of outcome more effectively than trials of non-pharmacological interventions. CONCLUSION: Some imaginative solutions to the logistic difficulties of conducting randomized trials in general practice were noted. These may serve as an incentive to those undertaking such studies in the future.

Community Health Services↗

PubMed2001

Growth hormone improves clinical status in prepubertal children with cystic fibrosis: results of a randomized controlled trial.

OBJECTIVES: We conducted a 1-year randomized controlled trial to test the hypothesis that growth hormone (GH) improves the clinical status of children with cystic fibrosis. STUDY DESIGN: Nineteen prepubertal children were randomized to control (NonTX, n = 9) or to daily injections of GH (0.3 mg/kg/wk) (GHTX, n = 10) for 1 year. Every 3 months height, weight, and lean tissue mass were measured. Caloric intake, resting energy expenditure, pulmonary function, and respiratory muscle strength were measured every 6 months, as were total number of hospitalizations and courses of outpatient intravenous antibiotics. RESULTS: The GHTX group had significantly greater height, height velocity (NonTX = 3.8 +/- 1.4 cm/y, GHTX = 8.1 +/- 2.4 cm/y; P =.002), weight, weight velocity (NonTX = 2.1 +/- 0.9 kg/y, GHTX = 4.5 +/- 1.1 kg/y; P =.004), and change in lean tissue mass (NonTX = 2.1 +/- 1.6 kg, GHTX = 4.7 +/- 1.7 kg; P =.01) analyzed by the Student t test. The GHTX group had significant improvement in delta forced vital capacity compared with the year before study, and respiratory muscle strength improved. The number of hospitalizations and outpatient intravenous antibiotic courses significantly decreased in the GHTX group but did not change in the NonTX group. No subject had development of cystic fibrosis-related diabetes. CONCLUSIONS: Results of the first randomized controlled trial of GH treatment in cystic fibrosis indicate that GH improves growth and clinical status.

Body Composition↗

PubMed2003

Efficacy of dry extract of ivy leaves in children with bronchial asthma--a review of randomized controlled trials.

OBJECTIVES: To investigate if extracts from dried ivy leaves (Hedera helix L.) are effective in the treatment of chronic airway obstruction in children suffering from bronchial asthma. DESIGN: Systematic review of trials documented in the literature with re-analysis of original data. TRIALS: 5 randomized controlled trials investigating the efficacy of ivy leaf extract preparations in chronic bronchitis, 3 of which were conducted in children and met our selection criteria. One compared ivy leaf extract cough drops to placebo, one compared suppositories to drops and one tested syrup against drops. MAIN OUTCOME MEASURES: Body-plethysmographic and spirometric measures. RESULTS: Drops were significantly superior to placebo in reducing airway resistance (primary outcome measure; p = 0.04 two-sided) and descriptively superior in all other 'objective' measures. For syrup and suppositories, at least 54%, resp. 35% of the effect against placebo were preserved. CONCLUSIONS: The trials included in this review indicate that ivy leaf extract preparations have effects with respect to an improvement of respiratory functions of children with chronic bronchial asthma, but more far-reaching conclusions can hardly be drawn because of a meagre database, including the fact that only one primary trial included a placebo control. Further research, particularly into the long-term efficacy of the herbal extract, is needed.

Asthma↗

PubMed2001

Randomized, controlled trials in surgery: perceived barriers and attitudes of Australian colorectal surgeons.

PURPOSE: Although the randomized, controlled trial has gained preeminence as the criterion standard for evaluating pharmaceutical treatments, randomized controlled trials in surgery have been perceived as difficult to surmount. Furthermore, attitudes of surgeons toward randomized, controlled trials are not well understood. We determined the views of Australian surgeons about feasibility of and barriers to surgical randomized trials. METHODS: All members of the Section of Colon and Rectal Surgery of the Royal Australasian College of Surgeons (n = 147) and all Australian colorectal subspecialist surgeons (n = 72) were mailed a questionnaire that included questions about surgical randomized, controlled trials. RESULTS: A total of 195 surgeons responded (89 percent). Two-thirds (66.7 percent; 95 percent confidence interval 59.5-73.1) of respondents agreed that "Randomized controlled trials should be the study design of choice" to evaluate new surgical procedures. Only 19 percent (95 percent confidence interval 13.9-25.3) endorsed the statement that "too much emphasis is placed on results of randomized controlled trials." Barriers to conducting surgical randomized, controlled trials identified by the majority included insufficient funding (74.4 percent; 95 percent confidence interval 67.5-80.2), a lack of support from the wider surgical community (55.9 percent; 95 percent confidence interval 48.6-62.9), and difficulties in convincing patients to accept random allocation to treatment (62.6 percent; 95 percent confidence interval 55.3-69.3). CONCLUSION: These results reveal positive attitudes among Australian surgeons toward randomized, controlled trials, although concerns about the feasibility of randomized, controlled trials have been reinforced.

Adult↗

PubMed1990

Captopril improves hemodynamic response to static exercise in patients with congestive heart failure: a double-blind, placebo-controlled, randomized trial.

Systemic and peripheral hemodynamic response to isometric exercise by handgrip test at 30% maximal voluntary contraction (MVC) for 3 minutes was assessed in 16 patients with congestive heart failure (CHF) after short-term treatment with either captopril or placebo given according to a double-blind, randomized, cross-over sequence. During placebo, isometric exercise increased blood pressure (BP) and total peripheral vascular resistance (TPVR) and decreased cardiac index (CI). Captopril reduced the pressor response to exercise (mean +/- SD) (% systolic: from 14.7 +/- 6 to 11.7 +/- 3; p less than .05/% diastolic: from 12.4 +/- 4 to 8 +/- 3; p less than .005) and increased CI (from 2.3 +/- .6 to 2.6 +/- .9 liters/min/m2; p less than .01) whereas TPVR remained virtually unchanged (from 1479 +/- 597 to 1594 +/- 692 U; NS). The changes in mean BP after exercise were inversely related to the early increase in forearm blood flow (FBF) in exercising forearm during both placebo (r = .67) and captopril (r = .71). The extent of reduction in mean BP response after captopril was inversely related to the extra increase in exercising FBF determined by the drug when compared to placebo (r = .73). We conclude that captopril is able to improve the hemodynamic response to static exercise in patients with CHF, probably by increasing the blood supply to exercising muscles during contraction, thus blunting the extent of reflex pressor response.

Blood Pressure↗

PubMed1998

The reduction of chronic nonspecific low back pain through the control of early morning lumbar flexion. A randomized controlled trial.

STUDY DESIGN: Eighteen-month, randomized controlled trial with partial crossover. OBJECTIVES: To test the hypothesis that the control of lumbar flexion in the early morning will significantly reduce chronic, nonspecific low back pain. SUMMARY OF BACKGROUND DATA: Previous studies have indicated an increased risk of low back pain with bending forward in the early morning, primarily because of increased fluid content in the intervertebral discs at that time. METHODS: After 6 months of recording baseline data, 85 subjects with persistent or recurring low back pain were randomly assigned to treatment and control groups. The treatment group received instruction in the control of early morning lumbar flexion. The control group received a sham treatment of six exercises shown to be ineffective in reducing low back pain. Six months later, the control group received the experimental treatment, Diaries were used to record daily levels of pain intensity, disability, impairment, and medication usage. RESULTS: Significant reductions in pain intensity (P < 0.01) were recorded for the treatment group, but not for the control group (point estimate, 33%; 95% confidence interval, 11-55%). After receiving the experimental treatment, the control group responded with similar reductions (P < 0.05). Significant reductions also were observed in total days in pain, disability, impairment, and medication usage. CONCLUSIONS: Controlling lumbar flexion in the early morning is a form of self-care with potential for reducing pain and costs associated with chronic, nonspecific low back pain.

Activities of Daily Living↗

PubMed1988

Cyclosporin-induced remission of IDDM after early intervention. Association of 1 yr of cyclosporin treatment with enhanced insulin secretion. The Canadian-European Randomized Control Trial Group.

A randomized double-blind placebo-controlled trial was undertaken to determine whether cyclosporin enhances remission of insulin-dependent diabetes mellitus (IDDM) through the 1st yr after diagnosis. Dosage with insulin was minimized with target control of blood glucose levels less than or equal to 7.8 mM (140 mg/dl) before meals. Metabolic control was evaluated by serial determinations of glycosylated hemoglobin levels, and endogenous secretion of insulin was evaluated by determination of the levels of glucagon-stimulated insulin-connecting peptide (CP) in the plasma at 3-mo intervals. A compound definition of remission required a glucagon-stimulated CP level in plasma greater than or equal to 0.6 nM or a non-insulin-receiving state (NIR) in which target control of glycemia was maintained without administration of insulin. A clinical definition of remission required only the NIR state as defined. One hundred eighty-eight patients aged 10-35 yr entered the study within 6 wk of initiation of insulin therapy and within 14 wk of onset of symptoms and were studied for 1 yr. There were no significant differences in metabolic control between the two treatment groups during the study. The anticipated adverse effects of cyclosporin were not more frequent or severe than in other experience with the drug, but histological changes attributable to cyclosporin were present in some kidney biopsies obtained from selected patients after 1 yr. At 1 yr, by the compound definition, 33% of the cyclosporin-group and 21% of the placebo-group patients were in remission, when the corresponding rates for NIR remissions were 24 and 10%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1989

Prospective, controlled, randomized trial of naloxone infusion in early hyperdynamic septic shock.

To determine whether naloxone infusion is efficacious in severe hyperdynamic septic shock, we conducted a prospective study of 22 patients randomly assigned to a naloxone or placebo group. Patients were treated 12 +/- 2 h (SEM) after the onset of shock, with a mean arterial pressure (MAP) of 63 +/- 3 mm Hg. All patients had clinical evidence of an infectious process and required dopamine 20 +/- 2 micrograms/kg.min. Five (46%) of 11 patients in the naloxone group and one (9%) of the other 11 patients in the placebo group responded clinically. The MAP among the five responders increased from 62 +/- 5 to 89 +/- 4 mm Hg within 20 min of naloxone treatment (p less than .01). This favorable hemodynamic response was sustained throughout the patients' clinical course. In contrast, the MAP did not change significantly in the nonresponders who received naloxone, nor did it change in the placebo group. More patients in the naloxone group than in the placebo group received steroids concurrently. Survival rate was 100% in those who responded to naloxone clinically. However, overall survival rate in each group was essentially the same. No adverse effects were observed, except for mild agitation in some of the patients receiving naloxone. We conclude that naloxone infusion is clinically efficacious in improving the hemodynamic profile of a subgroup of patients with severe early hyperdynamic septic shock, but does not appear to improve the overall survival rate.

Aged↗

PubMed2002

Blind faith? The effects of promoting active sick leave for back pain patients: a cluster-randomized controlled trial.

STUDY DESIGN: A cluster-randomized controlled trial. OBJECTIVE: To evaluate the effects of two strategies to increase the use of active sick leave (ASL) among patients with low back pain (LBP) on improved return to work and quality of life. SUMMARY OF BACKGROUND DATA: Active sick leave is an option provided by the Norwegian National Insurance Administration that enables employees to return to modified duties at the workplace with 100% of normal wages. A proactive implementation strategy increased the use of ASL for LBP patients from 11.5% to 17.7% compared with a passive intervention and a control group ( = 0.006). METHODS: Sixty-five municipalities were randomly assigned to a passive intervention, a proactive intervention, or a control group. The interventions, which were designed to improve the use of ASL, were targeted at patients on sick leave for LBP for more than 16 days (n = 6179), their general practitioners, employers, and local insurance officers. The main outcome measures were the average number of days off work, the proportion of patients returning to work within 1 year, and self-reported quality of life while on sick leave. RESULTS: The median number of days on sick leave was similar in the proactive intervention group (70 days), the passive intervention group (68 days), and the control group (71 days) ( = 0.8). The proportion of patients returning to work before 50 weeks was also similar in the proactive (89%), passive (89.5%), and control groups (89.1%). Response rates for the questionnaires that were sent to patients were low (38%), and no significant differences were observed across the three groups for quality of life or patient satisfaction. CONCLUSIONS: It is not likely that efforts to increase the use of ASL will result in measurable economic benefits or improved health outcomes at the population level. The benefits of ASL for individual patients with LBP are not known.

Back Pain↗

PubMedDate not supplied

Side effects of mefloquine prophylaxis for malaria: an independent randomized controlled trial.

A prospective randomized double-'blind' trial was undertaken during a military exercise in East Africa to determine whether there was a significant difference in the incidence of side effects experienced by soldiers taking mefloquine 250 mg weekly compared with those taking chloroquine 300 mg weekly and proguanil 200 mg daily as chemoprophylaxis for malaria. Subject to their informed voluntary consent, male soldiers who were not aviators were included in the study. Identical questionnaires were completed voluntarily at the end of 2 and 8 weeks. Symptoms were classified by nature into-'all', 'neuropsychological', 'enteric' and 'other', and by severity into 'severe' and 'very severe'. The proportions of respondents experiencing side effects were compared to seek statistically significant differences between the chemoprophylactic groups. Questionnaire 1 was completed after 2 weeks by 183 of 317 subjects (58%) randomly assigned mefloquine and by 176 of 307 subjects (57%) randomly assigned chloroquine-proguanil. The incidence of putative side effects was not significantly different between the groups (71/183 vs. 70/176), odds ratio 0.96 (95% confidence interval [CI] 0.63 to 1.47). Questionnaire 2 was completed after 8 weeks by 145 of 317 subjects (46%) randomly assigned mefloquine and by 142 of 307 subjects (46%) randomly assigned chloroquine-proguanil. The incidence of putative side effects was still not significantly different between the groups (95/145 vs. 103/142), odds ratio 0.72 (95% CI 0.43 to 1.19). None of the subjects developed a serious neuropsychological reaction. Among respondents, 12.8% and 38% admitted lack of full compliance at 2 and 8 weeks, respectively. Exclusion of these subjects during a secondary analysis did not affect the results. None of the subjects developed malaria in the 12 months following return to the UK. Subject to the limitations of a response rate that was smaller than desired and the fact that the study was conducted in fit male military personnel, these results support evidence which indicates that mefloquine is no more toxic than chloroquine-proguanil.

Africa, Eastern↗

PubMed1979

Cimetidine for anastomotic ulcers after partial gastrectomy. A randomized controlled trial.

In a randomized double-blind multicenter trial, 15 outpatients with endoscopically proved anastomotic ulceration after Billroth I or Billroth II partial gastrectomy received cimetidine, 1 g daily over eight weeks, or a placebo. All patients also received antiacid. The ulcer healed completely in all seven cimetidine-treated patients and in one of the eight placebo-treated patients (P less than 0.01). Ulcers not healed during the double-blind phase of the trial were all subsequently healed on open cimetidine treatment. There was a trend toward improvement of daytime symptoms in favor of cimetidine (P = 0.06), and nighttime symptoms were significantly relieved during the initial four weeks of cimetidine treatment P = 0.02). We conclude that cimetidine, 1 g daily, promotes healing of anastomotic ulcers after partial gastrectomy.

Adult↗

PubMed1998

Transarterial embolization versus symptomatic treatment in patients with advanced hepatocellular carcinoma: results of a randomized, controlled trial in a single institution.

This randomized, controlled trial assessed the effect of transarterial embolization (TAE) (without associated chemotherapy) on the survival of patients with nonsurgical hepatocellular carcinoma (HCC). Eighty consecutive patients were randomized to treatment with embolization (Group A, n = 40), or to symptomatic treatment (Group B, n = 40), there being no differences between both groups regarding the degree of liver function impairment and tumor stage. Eighty-two percent of the patients presented a self-limited postembolization syndrome, without treatment-related mortality. Fifty-five percent of the treated cases exhibited a partial response, which resulted in a lower probability of tumor progression during follow-up (57% vs. 77% at 1 year; P < .005). However, after a median follow-up of 24 months (30 deaths in each group), there are no differences in survival (Group A: 49% and 13%; Group B: 50% and 27%, at 2 and 4 years, respectively; P = .72). The absence of differences was maintained even when dividing patients according to Child-Pugh's grade, Okuda stage, or performance status test (PST). Furthermore, there were no differences in the probability of complications or in the need of hospital admissions. In conclusion, TAE has a marked antitumoral effect associated to a slower growth of the tumor, but it does not improve the survival of patients with nonsurgical HCC.

Aged↗

PubMed2001

Conducting randomized, controlled trials. Experience with the dysfunctional uterine bleeding intervention trial.

OBJECTIVE: To conduct a randomized, controlled trial (RCT) to examine issues associated with therapeutic alternatives to standard hysterectomy for women with dysfunctional uterine bleeding. STUDY DESIGN: Participants were to be randomly assigned to one of three treatment groups: hysterectomy, endometrial ablation and medical management. Recruitment was targeted at 375 women. RESULTS: Despite multiple recruitment strategies, recruitment was weak, with only five women enrolled after six months. Providers and women screened for eligibility often expressed discomfort with randomization. The protocol was amended to an elective treatment cohort design with a randomization component. Recruitment improved, with 37 women enrolled after four months. CONCLUSION: The success of RCTs may be affected by multiple factors. Acceptance of the protocol by patients and providers is essential. The RCT may present providers with a conflict between the goals of research and of providing optimal individualized care. Thus, RCTs may not always be appropriate for studies designed to examine best treatments in clinical practice, and nonrandomized designs may provide appropriate alternatives in some cases.

Clinical Protocols↗

PubMed1990

Intravenous recombinant tissue-type plasminogen activator in patients with unstable angina pectoris. Results of a placebo-controlled, randomized trial.

Because thrombus formation may contribute to coronary obstruction in patients with unstable angina pectoris, we performed a pilot investigation to determine whether thrombolytic therapy can relieve coronary narrowing in this acute ischemic syndrome. Sixty-seven patients with rest angina and angiographic evidence of coronary stenosis were randomly assigned to receive either low-dose intravenous recombinant tissue-type plasminogen activator (rt-PA) (0.75 mg/kg over 1 hour), high-dose intravenous rt-PA (0.75 mg/kg over 1 hour; total dose, 100 mg over 6 hours), or intravenous placebo followed by repeat coronary angiography at 24-48 hours to assess change in the severity of coronary narrowing. Each patient also received oral aspirin and intravenous heparin. Mean values of coronary stenosis severity (percent of diameter reduction) declined to a similar extent in each group: placebo, 75 +/- 14% to 72 +/- 14% (p = 0.07); low-dose rt-PA, 75 +/- 16% to 71 +/- 18% (p = 0.03), and high-dose rt-PA, 82 +/- 11% to 77 +/- 17% (p = 0.18), with only the low-dose rt-PA group achieving statistical significance. Resolution of intracoronary filling defects, increase in antegrade flow grade, or both also occurred equally among the three groups. There was considerable variation in individual patient response. Between 29% and 50% of patients within each group demonstrated a decrease in stenosis severity, whereas 50% to 57% noted either improvement in antegrade flow or resolution of intracoronary thrombus. There was no difference in incidence of major bleeding events among the three groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1989

Quality assessment of randomized controlled trials of contrast media.

Numerous randomized controlled trials (RCTs) have been conducted to define the relative benefits of low-osmolality contrast media (LOM) and high-osmolality contrast media (HOM). Because of the clinical and economic significance of the conclusions drawn from these RCTs, the authors used a standardized instrument to evaluate the quality of study design and data analysis of 100 RCTs published between 1982 and 1987 that compared LOM and HOM. The mean quality score (+/- standard deviation) was 39 +/- 12 (maximum possible score, 100). The largest number of patients studied in any RCT was 435; the smallest was five. A majority of the RCTs received high scores on three attributes of quality, intermediate scores on seven, and low scores on nine. These results underscore the difficulty of designing, performing, analyzing, and reporting high-quality RCTs. Nevertheless, limitations in study design and data analysis need to be considered when interpreting results of these RCTs. Future RCTs comparing LOM and HOM should be performed with greater attention to basic elements of good study design and data analysis.

Clinical Trials as Topic↗