72 resultados para Randomized Clinical Trials
Resumo:
Observational longitudinal research is particularly useful for assessing etiology and prognosis and for providing evidence for clinical decision making. However, there are no structured reporting requirements for studies of this design to assist authors, editors, and readers. The authors developed and tested a checklist of criteria related to threats to the internal and external validity of observational longitudinal studies. The checklist criteria concerned recruitment, data collection, biases, and data analysis and descriptive issues relevant to study rationale, study population, and generalizability. Two raters independently assessed 49 randomly selected articles describing stroke research published from 1999 to 2003 in six journals: American Journal of Epidemiology, Journal of Epidemiology and Community Health, Stroke, Annals of Neurology, Archives of Physical Medicine and Rehabilitation, and American Journal of Physical Medicine and Rehabilitation. On average, 17 of the 33 checklist criteria were reported. Criteria describing the study design were better reported than those related to internal validity. No relation was found between study type (etiologic or prognostic) or word count and quality of reporting. A flow diagram for summarizing participant flow through a study was developed. Editors and authors should consider using a checklist and flow diagram when reporting on observational longitudinal research.
Resumo:
The prevention of some mental disorders in young people appears to be possible. Several small and medium randomised controlled trials show that some anxiety, affective and substance-use disorders can be prevented. These trials show that the interventions are efficacious, but whether they will be effective in routine practice is not known. The evidence is sufficiently good to warrant a large community trial in which the roll-out is staged and school communties evaluated before and after the roll-out.
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Until recently, spironolactone was considered only as an antagonist at the aldosterone receptors of the epithelial cells of the kidney and was used clinically in the treatment of hyperaldosteronism and, occasionally, as a K+-sparing diuretic. The spironolactone renaissance started with the experimental finding that spironolactone reversed aldosterone-induced cardiac fibrosis by a cardiac action. Experimentally, spironolactone also has direct effects on blood vessels. Spironolactone reduces vascular fibrosis and injury, inhibits angiogenesis, reduces vascular tone and reduces portal hypertension. The rationale for the Randomized Aldactone Evaluation Study (RALES) of spironolactone in heart failure was that ‘aldosterone escape’ occurred through non-angiotensin II mechanisms. The RALES clinical trial was stopped early when it was shown that there was a 30% reduction in risk of death among the spironolactone patients. In RALES, spironolactone also reduced hospitalisation for worsening heart failure and improved the symptoms of heart failure. Other recent clinical trials have shown that spironolactone reduces cardiac and vascular collagen turnover, improves heart variability, reduces ventricular arrhythmias, improves endothelial dysfunction and dilates blood vessels in human heart failure and these effects probably all contribute to the increased survival in heart failure. Spironolactone may also be useful in the treatment of left ventricular hypertrophy, portal hypertension and cirrhosis. There have also been some recent small clinical trials of spironolactone as an anti-androgen showing potential in acne, hirsutism and precocious puberty.
Resumo:
Tissue type plasminogen activator is available, through recombinant technology, for thrombolytic use as alteplase. Alteplase is relatively clot specific and should cause less bleeding side effects than the non-specific agents such as streptokinase. Alteplase has been used successfully in evolving myocardial infarction (MI) to reopen occluded coronary arteries. It is probably equally effective or superior to streptokinase in opening arteries and reducing mortality in Mi. Alteplase is most effective when given early in Mi and is probably ineffective when given 12 h after the onset of symptoms. The effectiveness of alteplase in Mi can be increased by front loading with a bolus of 15 mg, followed by an infusion of 50 mg over 30 min and 35 mg over 60 min. Percutaneous transluminal coronary angioplasty or stenting is associated with a greater patency and lower rates of serious bleeding, recurrent ischaemia and death than alteplase in MI and is likely to take over from alteplase as the standard Mi treatment. A reduced dose of alteplase to increase coronary artery patency prior to angioplasty may be useful in Mi. An exciting new indication for the use of alteplase is in stroke, where it has become the first beneficial intervention. Alteplase is used to reopen occluded cerebral vessels but is associated with an increased risk of intracerebral haemorrhage. Alteplase is beneficial if given within 3 h of the onset of stroke but not after this time period. Therefore, the next challenge is to increase the percentage of people being diagnosed and treated within this period. Clinical trials have not established a role for alteplase in the treatment of acute coronary syndromes or deep vein thrombosis. However, alteplase is useful in treating pulmonary thromboembolism and peripheral vascular disease.
Resumo:
Objective: To develop a reliable, valid, and responsive self-administered questionnaire to probe pain, stiffness and physical disability in patients with osteoarthritis (OA) of the hand. Design: In order to assess the dimensionality of the symptomatology of hand OA, a self-administered questionnaire was developed to probe various aspects of pain (10 items), stiffness (two items), and physical function (83 items). The question inventory was generated from eight existing health status measures and an interactive process involving four rheumatologists, two physiotherapists, and an orthopaedic surgeon. Results: Face-to-face interviews were conducted with 50 OA hand patients; 39 females and 11 males with mean age 62.8 years and mean disease duration 9.4 years. Items retained were those which fulfilled specified selection criteria: prevalence greater than or equal to60% and mean importance score approximating or exceeding 2.0 Item exclusion criteria included low prevalence, gender-based, ambiguous, duplicates or similarities, alternatives, composite items, and items that were too restrictive. This process resulted in five pain, one stiffness and nine function items which have been proposed for incorporation in the AUSCAN Index. Conclusions: Using a traditional development strategy, we have constructed a self-administered multi-dimensional outcome measure for assessing hand OA. The next stage includes reliability, validity and responsiveness testing of the 15-item questionnaire. (C) 2002 OsteoArthritis Research Society Intenational. Published by Elsevier Science Ltd. All rights reserved.
Resumo:
Objective. Outcome assessment in clinical trials using the Western Ontario and McMaster University (WOMAC 3.0) Osteoarthritis Index is traditionally achieved through self-administration of the Index. However, in other areas of clinical measurement, telephone administration has been shown to be a reliable method of acquiring data that are both accurate and complete. To address this issue in knee osteoarthritis (OA), we conducted a comparative study of telephone administration by interviewer of WOMAC LK3.0 versus onsite self-completion at the hospital. Methods. Fifty consenting patients with knee OA were randomized to complete the WOMAC LK3.0 Index by telephone interview one day, followed by onsite completion the following day, or vice versa. Neither patients nor interviewers had access to any prior scores. Results. The mean age of the 50 patients was 66.3 years (range 44-82); 34 (68%) were female and 16 (32%) male. There was excellent agreement between the mean office and telephone scores, with mean differences for the WOMAC LK3.0 pain, stiffness, and function subscale scores and total score of 0.09, 0.12, 0.78, and 0.98, respectively. These differences were well within the respective protocol defined equivalence criteria of +/- 1.7, +/- 0.9, +/- 6.4, and +/- 9.1, and represented differences from office scores of 0.9, 2.6, 2.4, and 2.2%, respectively. Conclusion. The use of telephone interviews for the WOMAC LK3.0 Index is a valid method of obtaining OA outcome measurements. These observations have important implications for designing data acquisition strategies for future OA clinical trials and for longterm observational studies.
Resumo:
A spectrum of anti-inflammatory properties, evidence of anti-infective action against Pseudomonas aeruginosa at sub-inhibitory concentrations and positive clinical experience in patients with diffuse panbronchiolitis, a disease with features in common with cystic fibrosis (CF), has prompted research to evaluate the role of macrolide therapy in patients with CF. Newer macrolides such as azithromycin have the advantage of improved tolerability and a prolonged intracellular half-life requiring an infrequent dosing regimen. Results from initial studies suggest a benefit from several months of macrolide therapy in patients with CF. An improvement in lung function was initially shown in a small open study in children, while maintenance of lung function compared with placebo, reduced acute respiratory exacerbations, and reduced systemic markers of inflammation were demonstrated in a randomized, placebo-controlled study of macrolide therapy in adult patients with CF. Additional controlled studies are required to determine optimal drug, dosage, and duration of therapy, and long-term adverse effects of prolonged therapy with macrolides in patients with CF. The potential, with long-term use, to induce resistance against other bacteria colonizing the upper respiratory tract e.g. pneumococci has not been explored. Measurement of cytokines and inflammatory mediators from the sputum of patients with CF is technically difficult and does not correlate with disease activity. There is a need for easily measurable, reproducible and clinically meaningful end-points for evaluation of new therapies in CF. The choice of appropriate outcome measures, apart from lung function, to monitor disease activity needs careful consideration in clinical trials determining the efficacy of macrolides in patients with CF. Evidence-based recommendations for the use of macrolides in the treatment of CF are not expected for some years although macrolides are already being prescribed for long-term use in some centers. There is a need for further research into mechanisms of anti-inflammatory action of macrolides in the lungs of patients with CF and whether or not such therapy may be beneficial in the long term. Copyright 2002 Adis International
Resumo:
Manual therapy, exercise and education target distinct aspects of chronic low back pain and probably have distinct effects, This study aimed to determine the efficacy of a combined physiotherapy treatment that comprised all of these strategies. By concealed randomisation, 57 chronic low back pain patients were allocated to either the four-week physiotherapy program or management as directed by their general practitioners, The dependent variables of interest were pain and disability. Assessors were blind to treatment group. Outcome data from 49 subjects (86%) showed a significant treatment effect. The physiotherapy program reduced pain and disability by a mean of 1.5/10 points on a numerical rating scale (95% CI 0.7 to 2.3) and 3.9 points on the 18-point Roland Morris Disability Questionnaire (95% CI 2 to 5.8), respectively. The number needed to treat in order to gain a clinically meaningful change was 3 (95% CI 3 to 8) for pain, and 2 (95% CI 2 to 5) for disability. A treatment effect was maintained at one-year follow-up. The findings support the efficacy of combined physiotherapy treatment in producing symptomatic and functional change in moderately disabled chronic low back pain patients.
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Background: Augmentation strategies in schizophrenia treatment remain an important issue because despite the introduction of several new antipsychotics, many patients remain treatment resistant. The aim of this study was to undertake a systematic review and meta-analysis of the safety and efficacy of one frequently used adjunctive compound: carbamazepine. Data sources and study selection: Randomized controlled trials comparing carbamazopine (as a sole or as an adjunctive compound) with placebo or no intervention in participants with schizophrenia or schizoaffective disorder were searched for by accessing 7 electronic databases, cross-referencing publications cited in pertinent studies, and contacting drug companies that manufacture carbamazepine. Method: The identified studies were independently inspected and their quality assessed by 2 reviewers, Because the study results were generally incompletely reported, original patient data were requested from the authors; data were received for 8 of the 10 randomized controlled trials included in the present analysis, allowing for a reanalysis of the primary data. Dichotomous variables were analyzed using the Mantel-Haenszel odds ratio and continuous data were analyzed using standardized mean differences, both specified with 95% confidence intervals. Results: Ten studies (total N = 283 subjects) were included. Carbamazepine was not effective in preventing relapse in the only randomized controlled trial that compared carbamazepine monotherapy with placebo. Carbamazepine tended to be less effective than perphenazine in the only trial comparing carbamazepine with an antipsychotic. Although there was a trend indicating a benefit from carbamazepine as an adjunct to antipsychotics, this trend did not reach statistical significance. Conclusion: At present, this augmentation strategy cannot be recommended for routine use. The most promising targets for future trials are patients with excitement, aggression, and schizoaffective disorder bipolar type.
Resumo:
OTseeker (Occupational Therapy Systematic Evaluation of Evidence) is a new resource for occupational therapists that has been designed with the principle aim of increasing access to research to support clinical decisions. It contains abstracts of systematic reviews and quality ratings of randomized controlled trials (RCTs) relevant to occupational therapy. It is available, free of charge, at www.otseeker.com. This paper describes the OTseeker database and provides an example of how it may support occupational therapy practice.
Resumo:
The design of randomized controlled trials entails decisions that have economic as well as statistical implications. In particular, the choice of an individual or cluster randomization design may affect the cost of achieving the desired level of power, other things being equal. Furthermore, if cluster randomization is chosen, the researcher must decide how to balance the number of clusters, or sites, and the size of each site. This article investigates these interrelated statistical and economic issues. Its principal purpose is to elucidate the statistical and economic trade-offs to assist researchers to employ randomized controlled trials that have desired economic, as well as statistical, properties. (C) 2003 Elsevier Inc. All rights reserved.