Randomized controlled trial

About: Randomized controlled trial is a research topic. Over the lifetime, 119828 publications have been published within this topic receiving 4861808 citations. The topic is also known as: RCT & randomized control trial.

Outcome criteria in smoking cessation trials: proposal for a common standard

Abstract: Smoking cessation treatment is now integrated into many health-care systems and a major research effort is under way to improve current success rates. Until now results from randomized clinical trials have been reported in many different ways, leading to problems of interpretation. We propose six standard criteria comprising the 'Russell Standard' (RS). These criteria are applicable to trials of cessation aids where participants have a defined target quit date and there is face-to-face contact with researchers or clinic staff, as follows. (1) Follow-up for 6 months (RS6) or 12 months (RS12) from the target quit date or the end of a predefined 'grace period'; (2) self-report of smoking abstinence over the whole follow-up period allowing up to five cigarettes in total; (3) biochemical verification of abstinence at least at the 6-month or 12-month follow-up point; (4) use of an 'intention-to-treat' approach in which data from all randomized smokers are included in the analysis unless they have died or moved to an untraceable address (participants who are included in the analysis are counted as smokers if their smoking status at the final follow-up cannot be determined); (5) following-up 'protocol violators' and using their true smoking status in the analysis; and (6) collecting follow-up data blind to smokers' allocation to trial group. We believe that these criteria provide the best compromise between practicability and surrogacy for long-term cessation and will enable meaningful comparison between studies. There may be good reasons why other outcome criteria would also be reported, and studies that involve interventions with special groups or where there is no designated target quit date or face to face contact would need to adapt these criteria accordingly.

Randomized, Controlled Trial of Long-Term Moderate Exercise Training in Chronic Heart Failure: Effects on Functional Capacity, Quality of Life, and Clinical Outcome

Abstract: Background—It is still a matter of debate whether exercise training (ET) is a beneficial treatment in chronic heart failure (CHF) Methods and Results—To determine whether long-term moderate ET improves functional capacity and quality of life in patients with CHF and whether these effects translate into a favorable outcome, 110 patients with stable CHF were initially recruited, and 99 (59±14 years of age; 88 men and 11 women) were randomized into 2 groups One group (group T, n=50) underwent ET at 60% of peak Vo2, initially 3 times a week for 8 weeks, then twice a week for 1 year Another group (group NT, n=49) did not exercise At baseline and at months 2 and 14, all patients underwent a cardiopulmonary exercise test, while 74 patients (37 in group T and 37 in group NT) with ischemic heart disease underwent myocardial scintigraphy Quality of life was assessed by questionnaire Ninety-four patients completed the protocol (48 in group T and 46 in group NT) Changes were observed only in patients in group

Comparison of antiarrhythmic drug therapy and radiofrequency catheter ablation in patients with paroxysmal atrial fibrillation: A randomized controlled trial

Abstract: Context Antiarrhythmic drugs are commonly used for prevention of recurrent atrial fibrillation (AF) despite inconsistent efficacy and frequent adverse effects. Catheter ablation has been proposed as an alternative treatment for paroxysmal AF. Objective To determine the efficacy of catheter ablation compared with antiarrhythmic drug therapy (ADT) in treating symptomatic paroxysmal AF. Design, Setting, and Participants A prospective, multicenter, randomized (2:1), unblinded, Bayesian-designed study conducted at 19 hospitals of 167 patients who did not respond to at least 1 antiarrhythmic drug and who experienced at least 3 AF episodes within 6 months before randomization. Enrollment occurred between October 25, 2004, and October 11, 2007, with the last follow-up on January 19, 2009. Intervention Catheter ablation (n = 106) or ADT (n = 61), with assessment for effectiveness in a comparable 9-month follow-up period. Main Outcome Measures Time to protocol-defined treatment failure. The proportion of patients who experienced major treatment-related adverse events within 30 days of catheter ablation or ADT was also reported. Results At the end of the 9-month effectiveness evaluation period, 66% of patients in the catheter ablation group remained free from protocol-defined treatment failure compared with 16% of patients treated with ADT. The hazard ratio of catheter ablation to ADT was 0.30 (95% confidence interval, 0.19-0.47; P Conclusion Among patients with paroxysmal AF who had not responded to at least 1 antiarrhythmic drug, the use of catheter ablation compared with ADT resulted in a longer time to treatment failure during the 9-month follow-up period. Trial Registration clinicaltrials.gov Identifier: NCT00116428

The CONSORT statement: revised recommendations for improving the quality of reports of parallel-group randomized trials.

Abstract: To comprehend the results of a randomized, controlled trial (RCT), readers must understand its design, conduct, analysis, and interpretation. That goal can be achieved only through complete transparency from authors. Despite several decades of educational efforts, the reporting of RCTs needs improvement. Investigators and editors developed the original CONSORT (Con solidated S tandards o f R eporting T rials) statement to help authors improve reporting by using a checklist and flow diagram. The revised CONSORT statement presented in this paper incorporates new evidence and addresses some criticisms of the original statement. The checklist items pertain to the content of the Title, Abstract, Introduction, Methods, Results, and Discussion. The revised checklist includes 22 items selected because empirical evidence indicates that not reporting the information is associated with biased estimates of treatment effect or because the information is essential to judge the reliability or relevance of the findings. We intended the flow diagram to depict the passage of participants through an RCT. The revised flow diagram depicts information from four stages of a trial (enrollment, intervention allocation, follow-up, and analysis). The diagram explicitly includes the number of participants, for each intervention group, that are included in the primary data analysis. Inclusion of these numbers allows the reader to judge whether the authors have performed an intention-to-treat analysis. In sum, the CONSORT statement is intended to improve the reporting of an RCT, enabling readers to understand a trial's conduct and to assess the validity of its results.

The national lung screening trial: Overview and study design

Abstract: The National Lung Screening Trial (NLST) is a randomized multicenter study comparing low-dose helical computed tomography (CT) with chest radiography in the screening of older current and former heavy smokers for early detection of lung cancer, which is the leading cause of cancer-related death in the United States Five-year survival rates approach 70% with surgical resection of stage IA disease; however, more than 75% of individuals have incurable locally advanced or metastatic disease, the latter having a 5-year survival of less than 5% It is plausible that treatment should be more effective and the likelihood of death decreased if asymptomatic lung cancer is detected through screening early enough in its preclinical phase For these reasons, there is intense interest and intuitive appeal in lung cancer screening with low-dose CT The use of survival as the determinant of screening effectiveness is, however, confounded by the well-described biases of lead time, length, and overdiagnosis Despite previous attempts, no test has been shown to reduce lung cancer mortality, an endpoint that circumvents screening biases and provides a definitive measure of benefit when assessed in a randomized controlled trial that enables comparison of mortality rates between screened individuals and a control group that does not undergo the screening intervention of interest The NLST is such a trial The rationale for and design of the NLST are presented