Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Randomised controlled trials as topic”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,693 records · Page 94Linked to original sources
PubMed1995

[Clinical randomized controlled studies in anesthesiology according to quality guidelines of good clinical practice. 2: Principles of implementation, analysis, publication and evaluation].

This article was written to give researchers and clinicians a short synopsis of ethical and thorough design, conduct, analysis, publication, and interpretation of randomised controlled clinical trials according to the European quality standards of Good Clinical Practice (GCP). The paper consists of two parts. In the first part we introduce important elements of study design, especially study hypothesis, criteria of inclusion and study population, sample size calculation, validity considerations, bias and confounding, randomisation, stratification, and masking of treatment assignment. Different treatment allocation like multiple parallel groups, factorial experiment, cross-over, and sequential design are presented. Requirements of ethical standards according to the Declaration of Helsinki are discussed for their necessity in any experimentation in humans. Principles of informed consent are demonstrated with emphasis on special conditions in anaesthesia, emergency medicine, and intensive care research. In the second part of this article we explain issues of baseline assessment, experimental intervention, data recording, and data monitoring, particularly of negative or hazardous treatment effects. Topics of data analysis and reporting of trial results in publications are illustrated with regard to their influence on subsequent interpretation.

Anesthesiology↗
PubMed2000

Long-chain polyunsaturated fatty acid supplementation in infants born at term.

BACKGROUND: This section is under preparation and will be included in the next issue. OBJECTIVES: The n-3 and n-6 essential fatty acids alpha linolenic acid and linoleic acid are the precursors of the n-3 and n-6 longchain polyunsaturated fatty acids (LCPUFA). Controversy exists over whether LCPUFA are essential nutrients during infancy. The aim of this review is to assess whether supplementation of formula with LCPUFA is safe and of benefit to term infants. SEARCH STRATEGY: Trials were identified by MEDLINE, checking reference lists of articles and conference proceedings, and by personal communication. SELECTION CRITERIA: All randomised trials of formula supplemented with LCPUFA and with clinical endpoints were reviewed. DATA COLLECTION AND ANALYSIS: Eight randomised studies were identified. One of these studies was excluded due to supplementation commencing after three weeks of age, and one is awaiting assessment. The remaining six trials were assessed to be of good quality. MAIN RESULTS: Visual acuity was assessed by visual evoked potentials at 4 and 7-8 months in the studies of Makrides et al (1995 & 1996). The supplemented infants had an improved rate of visual maturation at both time points in the first study, but no difference was found between the groups at 4 months in the second study. Visual acuity was assessed by Teller acuity cards in the study of Carlson et al (1996), Clausen et al (1996) and Austed et al (1997). Supplementation had no consistent effect on visual acuity over the first year of life. General development was measured in five studies, all with small numbers. Two suggested a benefit of supplementation. One reported a benefit with supplementation at 4 months ( developmental quotient, DQ measured with the Brunet Lezine test, Agostini et al 1995), but when the groups were reassessed with the same test at 1 and 2 years, no differences were found in DQ (Agostini et al 1997). The other study reported a benefit with supplementation at 9 months (novelty preference measured by Fagan Infantest, Clausen et al 1996). The Adelaide studies showed no effect of supplementation on DQ at one year (Bayley Scales of Infant Development (BSID), Makrides et al 1995 &1996). The Portland study showed no effect of supplementation on development at one year (BSID) or at three years (Stanford Binet IQ test). The Portland study showed no effect of supplementation on language development at one year (McArthur Communicative Development Inventory, Janowsky et al 1995) or at three years (Peabody Picture Vocabulary Test, Scott et al 1997). Growth was measured in a small number of infants in the studies of Makrides et al (1995 & 1996) and Austed et al (1997). There was no suggestion that LCPUFA supplementation reduced the growth of term infants. REVIEWER'S CONCLUSIONS: At present there is little evidence from randomised trials of LCPUFA supplementation to support the hypothesis that LCPUFA supplementation confers any benefit on visual or cognitive development. There are no data from the randomised trials presently available to indicate that LCPUFA supplements influence the growth of term infants.

Dietary Supplements↗
PubMed1990

Chemotherapy in advanced non-small cell lung cancer.

Chemotherapy in advanced non-small cell lung cancer (NSCLC) has been evaluated with response rate, survival and quality of life as criteria. The data were collected from 142 phase II and III trials. The three main conclusions are: (1) multivariate landmark analyses show that a response to chemotherapy has an independent significant value for prognosis, and all studies of chemotherapy vs. best supportive care show some survival benefit in favour of chemotherapy; (2) NSCLC patients are a heterogeneous group with a large variation of known and unknown prognostic factors, such as the treatment centre, for both response and survival; and (3) retrospective analysis of the data show that response rate and survival are significantly correlated at response rate over 30% and in limited disease patients. The following recommendations are made: (1) new drugs should be compared in randomised phase II trials with a standard active drug; (2) randomised phase III trials of single agents or best supportive care vs. combination chemotherapy should be repeated in a well-defined subgroup of patients with a high performance score and limited tumour load; and (3) the palliative effect of chemotherapy in randomised trials in patients with symptoms should be investigated with relief of symptoms and quality of life as endpoints.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

The place of high-dose therapy with haemopoietic stem cell transplantation in relapsed and refractory Hodgkin's disease.

Conventional salvage therapy in Hodgkin's disease is appropriate in patients who relapse after a first complete remission of greater than one year many of whom who will have good long term survival with no further therapy. Patients who do not achieve CR, who relapse within one year of CR1 or who have a second relapse will have a survival of less than 20% at 5 years and these patients are candidates for high dose therapy (HDT) and Autologous Bone Marrow Transplantation (ABMT) or a second line salvage protocol. Current published and registry data suggests that HDT and ABMT may be superior and there is data from one prospective randomized trial to support this view. The best practice of ABMT to be used in this context must be decided after consideration of; timing, status, source of haematological stem cells, use of haematopoietic growth factors (HGF's) and dose and scheduling of high dose therapy. Confirmatory randomised trials are still urgently required before the optimal strategy for the management of relapsed Hodgkin's disease is defined.

Antineoplastic Agents↗
PubMed2004

Single or multiple embryo transfer following in vitro fertilisation for improved neonatal outcome: a systematic review of the literature.

BACKGROUND: The aim of the current review was to determine if single versus two or more embryos, or double versus three or more embryos, transferred to the woman of a subfertile couple at in vitro fertilisation (IVF) maximises the likelihood of pregnancy, while minimising the likelihood of multiple pregnancy and adverse sequelae. METHODS: Studies were identified that reported maternal, infant and cost outcomes following embryo transfer at IVF. RESULTS: Three randomised trials and 17 cohort studies were included. From two randomised trials, single embryo transfer was found to result in decreased incidence of clinical pregnancy, multiple pregnancy and low birthweight. In the cohort studies for single embryo transfer compared with transfer of two or more embryos the incidence of live birth and singleton pregnancies was unchanged, and the incidence of multiple pregnancies and low birthweight was reduced. For double embryo transfer compared with the transfer of three or more embryos, the incidence of clinical pregnancy, live birth, preterm birth and low birthweight babies was reduced. CONCLUSIONS: Information on neonatal and maternal outcomes following transfer of different numbers of embryos is limited. Transfer of one embryo does not alter the likelihood of a singleton pregnancy or birth when compared to transfer of two or more embryos. Transfer of one or two embryos decreases the risk of a multiple pregnancy, preterm birth and low birthweight. Further large, well-designed randomised trials are required to provide maternal and neonatal outcomes of relevance to a couple undergoing IVF.

Australia↗
PubMed1996

Epidemiology, prevention and screening for prostate cancer.

Prostate cancer is a growing social problem. The economical impact is high and is likely to become greater in future years, not only because the number of patients diagnosed with prostatic neoplasias is increasing steadily, but also because of the promotion of screening programmes and the rise in the number of surgical procedures available. It can be concluded that, at the present stage, widespread implementation of screening cannot be recommended. The answer to the question of screening can only be provided by large randomised trials, comparing either screening versus no screening, or early versus delayed treatment in patients in whom early cancer is detected by screening.

Cost-Benefit Analysis↗
PubMed2002

[Opioid detoxication under general anesthesia].

Antagonist-precipitated opioid detoxification under general anaesthesia has been used extensively since its introduction in 1988. The use of antagonists was believed to shorten the detoxification period. Administration to opioid dependents is followed by a violent activation of the adrenergic system, which results in the development of an acute withdrawal syndrome in the patient. This is usually treated with clonidine. To reduce the subjective discomfort, the procedure is conducted under anaesthesia. From the existing literature, one may conclude that despite more than ten years of development there is currently no sufficient evidence of the effectiveness of antagonist-precipitated opioid detoxification under general anaesthesia conducted under modern anaesthesiological management. Randomised, clinical trials are necessary to document the advantages of this detoxification method as compared to conventional treatment.

Anesthesia, General↗
PubMed1998

Lowering blood homocysteine with folic acid based supplements: meta-analysis of randomised trials. Homocysteine Lowering Trialists' Collaboration.

OBJECTIVE: To determine the size of reduction in homocysteine concentrations produced by dietary supplementation with folic acid and with vitamins B-12 or B-6. DESIGN: Meta-analysis of randomised controlled trials that assessed the effects of folic acid based supplements on blood homocysteine concentrations. Multivariate regression analysis was used to determine the effects on homocysteine concentrations of different doses of folic acid and of the addition of vitamin B-12 or B-6. SUBJECTS: Individual data on 1114 people included in 12 trials. FINDINGS: The proportional and absolute reductions in blood homocysteine produced by folic acid supplements were greater at higher pretreatment blood homocysteine concentrations (P < 0.001) and at lower pretreatment blood folate concentrations (P < 0.001). After standardisation to pretreatment blood concentrations of homocysteine of 12 mumol/l and of folate of 12 nmol/l (approximate average concentrations for Western populations), dietary folic acid reduced blood homocysteine concentrations by 25% (95% confidence interval 23% to 28%; P < 0.001), with similar effects in the range of 0.5-5 mg folic acid daily. Vitamin B-12 (mean 0.5 mg daily) produced an additional 7% (3% to 10%) reduction in blood homocysteine. Vitamin B-6 (mean 16.5 mg daily) did not have a significant additional effect. CONCLUSIONS: Typically in Western populations, daily supplementation with both 0.5-5 mg folic acid and about 0.5 mg vitamin B-12 would be expected to reduce blood homocysteine concentrations by about a quarter to a third (for example, from about 12 mumol/l to 8-9 mumol/l). Large scale randomised trials of such regimens in high risk populations are now needed to determine whether lowering blood homocysteine concentrations reduces the risk of vascular disease.

Adult↗
PubMed2006

[Interactions between radiation and hormonal therapy in breast cancer: simultaneous or sequential treatment].

BACKGROUND: Combining radiation and hormone therapy (administration of selective estrogen receptor modulators) has become common clinical practice in recent years for receptor positive breast cancer. Little is known about a possible interaction of both treatment modalities if they are given simultaneously. Tamoxifen (antiestrogen molecule, triphenylethylene derivative) may theoretically render cancer cells less responsive to radiotherapy arresting hormone-receptor-positive cells in G0/G1 phase and increase the risk of breast and lung fibrosis stimulating the secretion of transforming growth factor beta in human fibroblasts. PURPOSE: This article reviews the published data to assess the impact of sequencing of hormonal and radiation therapy on outcomes in breast cancer. METHODS: Computerised searches for publications debating the sequencing of hormonal therapy relative to radiation therapy were done using MEDLINE data. RESULTS: Results of tamoxifen experiments with cell culture regarding radioprotection of tumour clonogens are conflicting. In contrast to in vitro results, in animal studies no protective effect of tamoxifen was observed. In one in vitro study, letrozole (non-steroid selective aromatase inhibitor) had a radiosensitizing effect on breast-cancer lines. No randomised clinical trials to date have studied sequencing of tamoxifen or other selective estrogen receptor modulators and radiotherapy. Results from retrospective clinical studies which included treatment arms with and without tamoxifen showed reduction in tumour recurrence with tamoxifen. Some of these studies have noted increased risk of lung and breast fibrosis with tamoxifen with radiotherapy. Results of three articles examined the effect of tamoxifen sequence showed no adverse effect on local control or survival in sequential versus concurrent tamoxifen and radiation patients. One of the three studies also assessed the risk of complications with respect to the timing of tamoxifen with radiotherapy. There was no difference in the rates of complications between the two groups. The association of radiation and selective aromatase inhibitors or aromatase inactivators has not been addressed in clinical studies. CONCLUSIONS: Combined application of tamoxifen and radiotherapy improves survival and local control in breast cancer. Available clinical studies do not indicate that the simultaneous application of tamoxifen and radiotherapy is disadvantageous, as was suggested by some of the in vitro studies. The risk of subcutaneous breast and lung fibrosis might be slightly increased if tamoxifen is given simultaneously with radiotherapy. Both treatment modalities should be started early after surgery. There is no sufficient evidence to withhold tamoxifen administration during irradiation of breast cancer. The issue of optimal sequencing of hormonal and radiotherapy should be addressed in randomised clinical trials.

Animals↗
PubMed2001

[Hormonal supplements for postmenopausal women: no evidence of protection against cardiovascular disease].

Atherothrombotic cardiovascular disease is a leading cause of death in women, especially in the postmenopause. It is controversial whether postmenopausal hormone replacement therapy is protective with regard to cardiovascular disease. On the one hand, observational studies consistently show that the risk of cardiovascular disease is 35 to 50% lower among users of hormonal replacement than among non-users. In addition, hormonal replacement is associated with an improvement of the lipid profile and several other potentially beneficial effects. On the other hand, two recent placebo-controlled randomised trials did not find evidence in favour of cardiovascular protection by hormonal replacement. This discrepancy may be explained by insufficient adjustment for lifestyle factors in observational studies and insufficient consideration of methodological flaws in experimental studies, both of which lead to an overestimation of the protective effect of hormonal replacement. Hormonal replacement may affect the pathophysiology of atherothrombosis in several ways, both positive and negative. Progress in this field requires the isolation of the positive effects.

Aged↗
PubMed2001

Field efficacy of a 10 per cent pyriproxyfen spot-on for the prevention of flea infestations on cats.

The clinical application of a new method for using the insect growth regulator, pyriproxyfen, for controlling flea populations in cat-owning homes is evaluated for the first time. In a multicentric, controlled and randomised trial, 107 flea-infested cats were treated with a minimum dose of 10 mg/kg bodyweight pyriproxyfen as a 10 per cent spot-on application on two occasions, with a three-month interval between doses. For comparison, 99 cats received lufenuron suspension orally, once a month, for six months. Flea counts decreased significantly over time in each group and were significantly lower in the pyriproxyfen group than in cats treated with the reference product. The percentage of 'zero-flea' cats increased from 49 per cent on day 30 to 88 per cent on day 180 in the pyriproxyfen group and from 30 to 71 per cent in the lufenuron group at the same time points (P<0.05). Appropriately timed topical applications of pyriproxyfen, therefore, offer a method of flea control in the domestic environment.

Administration, Cutaneous↗
PubMed2005

[Chemoradiotherapy and anal canal cancer].

Local control and sphincter preservation are the two challenges of anal canal cancer treatment. These tumors are radio- and chemo-sensitive and treatment moved from surgical approach, with abdominoperineal resection, to definitive radiation therapy with or without concurrent chemotherapy. Randomised trials proved the benefit of combined modality with chemoradiotherapy and of mitomycine C (MMC) compared with radiotherapy alone, with a toxic death rate of about 2%. Indications of chemoradiotherapy are locally advanced tumor T2 > or = 4 cm, T3-4 or N1-3 but the best modalities of combined treatment are still under debate. Standard chemotherapy is 5 flurouracile (5FU) + MMC, but cisplatinum (CDDP) is an effective and well tolerated substitute for MMC. Favourable results with CDDP-containing regimen in term of toxicity and carcinologic control have been reported in phase II and retrospective studies. Total radiation dose, overall duration of radiation therapy, duration of the gap and indications of additional boost are not clear, but it is demonstrated that overall duration of treatment should be as short as possible to improve the therapeutic radio. Phase II and III studies are ongoing, to evaluate the best chemotherapy regimen between 5FU+MMC and 5FU+CDDP, the benefit of neoadjuvant or maintenance chemotherapy and the interest of increased total dose. Next future could be the utilisation of oral 5FU. This article is a review of past randomised trials, phases II and retrospective study on radiochemotherapy of anal canal carcinoma.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2004

New strategies in anaemia management: ACORD (Anaemia CORrection in Diabetes) trial.

Anaemia is a key component of diabetic nephropathy, but its importance has only recently been recognised. Recombinant human erythropoietin (epoetin) is an established treatment for renal anaemia, and may help to reduce complications associated with diabetic nephropathy, such as cardiovascular disease. The limited experience with the use of epoetin in this patient group prompts the urgent need for clinical data on anaemia correction in early diabetic nephropathy, particularly with regard to benefits on cardiovascular risk reduction. The Anaemia CORrection in Diabetes (ACORD) study will investigate the effects of anaemia correction on cardiac structure and function in patients with early diabetic nephropathy. This 15-month multicentre study will recruit 160 adult patients with diabetes, mild or moderate chronic kidney disease (with creatinine clearance >or=30 ml/min at screening) and moderate anaemia (haemoglobin [Hb], 10.5-13.0 g/dl). Patients will be randomised to one of two groups: the early treatment group will receive subcutaneous epoetin beta (NeoRecormon) at study entry to maintain target Hb levels of 13-15 g/dl, while the control group will reflect current practice and will not receive epoetin therapy until Hb levels decline below 10.5 g/dl. The primary efficacy variable, change in left ventricular mass index, will be evaluated at 15 months following randomisation; secondary efficacy variables will include changes in cardiac structure and function over the study period. The ACORD study should provide valuable information on the benefits of anaemia correction in patients with early diabetic nephropathy. The study will also increase awareness of the importance of treating anaemia associated with diabetes.

Anemia↗
PubMed2004

[Calcaneal fractures--the most frequent tarsal fractures].

Operative treatment of intra-articular calcaneal fractures with anatomical reduction and early mobilisation has lead to a considerable improvement of the functional results of these severe injuries over the recent two decades. New tendencies like modified approaches tailored according to the vascular anatomy, arthroscopic control of joint reduction in conjunction with open or percutaneous procedures, early flap coverage for severe open fractures or closed fractures with full thickness skin necrosis, the use of interlocking plates that further minimises the need of bone grafting and subtalar arthrolysis at the time of hardware removal for fibrous overgrowth have the potential for further improvement of the outcome. The observation from several comparative studies that operative treatment leads to superior results in displaced intra-articular calcaneal fractures has been qualified in a recent prospective, randomised multicentre trial. This paper presents and the authors' experience with the demanding operative treatment of these fractures together with new developments aiming at improving the clinical results.

Arthroscopy↗
PubMed2001

Evidence-based medicine: how good is the evidence?

The "evidence" in EBM must be of high quality in order to be useful, but this is not always the case. Even the "gold standard" of evidence-based medicine, the randomised clinical trial, is bedevilled by low inclusion rates and potentially important recruitment biases. "Real world" trials often do not give the same results as these highly artificial controlled clinical studies. Meta-analysis, the next most important level of evidence in EBM, may be unreliable, sometimes giving different results to subsequent large randomised trials. There is a bias in the hypotheses tested in large clinical trials, as the costs involved are usually covered by commercially interested companies. For this reason, trials of non-patentable compounds or therapies of no commercial interest may not be performed. The process of journal review and publication is capricious, slow and may have a selection bias towards positive studies, meaning that communication channels for the "evidence" are often unsatisfactory. For many rarer conditions and situations, there is simply no "high level" evidence, such as in paediatrics and subspecialty surgery.

Bias↗
PubMed2002

[MUSTIC trial].

The atrio-bi-ventricular pacing has been used for hemodynamic improvement since 1994, and the MUSTIC trial is the first controlled study assessing this concept. It collected 67 patients with severe and stable heart failure with optimised medical therapy, with sinus rhythm and without any traditional indication for pacing. After two periods of three months with blinded randomisation and cross-over, the bi-ventricular pacing mode showed its superiority to the inactive mode concerning all study endpoints, for example with an improvement of the functional capacity of 23% assessed by the 6-minutes-walk test. Thus the MUSTIC trial opens up the way for morbidity and mortality studies.

Aged↗