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Effectiveness of Embedded Social Media Content on E-cigarette Attitudes and Behaviors: Results from a Randomized Control Trial.

BACKGROUND: This longitudinal randomized controlled trial examined the effects of anti-vaping social media content on e-cigarette attitudes and intentions among U.S. young adults (ages 18-24; n=3,400). METHODS: Targeted content was embedded directly into participants' social media feeds, with varying levels of impressions. RESULTS: Results indicate that increased exposure to anti-vaping messages significantly elevated perceived risk of harm (&#x3b2;=0.11, 95% CI: 0.03-0.20, p < .01) and social unacceptability of e-cigarette use (&#x3b2;=0.10, 95% CI: 0.03-0.18, p < .01), while decreasing intentions to vape (RRR = 0.59, 95% CI: 0.36-0.97, p < .05). Notably, these attitudinal shifts occurred even with relatively low ad exposure and over an extended intervention period, while controlling for the e-cigarette use status (never, former, or current) of participants. Discussion These findings support the effectiveness of digital media campaigns in influencing health-related behaviors and attitudes among young adults. Specifically, embedding anti e-cigarette content directly in the feed of young adults is shown to be effective in shifting attitudes in a space where these young adults are already engaged. Limitations include limited ad impressions and minimal change in ad awareness recall, suggesting future research should explore longer interventions and broader nicotine product messaging.

Humans↗

The effects of postmenopausal hormone therapies on female sexual functioning: a review of double-blind, randomized controlled trials.

Double-blind randomized controlled trials of estrogen and/or testosterone on sexual function among natural or surgical menopause in women are reviewed. Power, validity, hormone levels, and methodological issues were examined. Certain types of estrogen therapy were associated with increased frequency of sexual activity, enjoyment, desire, arousal, fantasies, satisfaction, vaginal lubrication, and feeling physically attractive, and reduced dyspareunia, vaginal dryness, and sexual problems. Certain types of testosterone therapy (combined with estrogen) were associated with higher frequency of sexual activity, satisfaction with that frequency of sexual activity, interest, enjoyment, desire, thoughts and fantasies, arousal, responsiveness, and pleasure. Whether specific serum hormone levels are related to sexual functioning and how these group effects apply to individual women are unclear. Other unknowns include long-term safety, optimal types, doses and routes of therapy, which women will be more likely to benefit from (or be put at risk), and the precise interplay between the two sex hormones.

Double-Blind Method↗

Nurse-Led Home-Based Mobile Health Cardiac Rehabilitation Program for Patients With Chronic Heart Failure: A Randomized Controlled Trial.

This 12-week randomized controlled trial evaluated a nurse-led mHealth intervention for patients with chronic heart failure, conceptually informed by Riegel's middle-range theory of self-care of chronic illness. The program integrated wearable activity tracking with weekly nurse-led behavioral coaching, reflecting the core self-care processes of monitoring, maintenance, and management. Compared with usual care, the intervention significantly improved daily step count, 6-minute walk distance, metabolic equivalents, and left ventricular ejection fraction. Findings highlight the effectiveness of theory-informed, nurse-delivered mHealth strategies in enhancing physical activity and cardiopulmonary function, while underscoring the critical role of advanced practice nurses in home-based chronic disease management.

Aged↗

Pharmacodynamic efficacy, clinical safety, and outcomes after prolonged platelet Glycoprotein IIb/IIIa receptor blockade with oral xemilofiban: results of a multicenter, placebo-controlled, randomized trial.

BACKGROUND: Parenteral administration of platelet glycoprotein IIb/IIIa (GP IIb/IIIa) receptor blockers can reduce ischemic complications of coronary angioplasty. Orally active GP IIb/IIIa blockers may allow more sustained receptor antagonism with the potential for long-term secondary prevention. The pharmacodynamic efficacy, clinical safety, and outcomes after prolonged receptor blockade with an orally active GP IIb/IIIa antagonist are not known. The Oral Glycoprotein IIb/IIIa Receptor Blockade to Inhibit Thrombosis (ORBIT) Trial is a multicenter, placebo-controlled, randomized trial of xemilofiban, an oral platelet GP IIb/IIIa blocking agent, administered to patients after percutaneous coronary intervention. METHODS AND RESULTS: After successful elective percutaneous coronary intervention, 549 patients were randomized to receive either placebo or xemilofiban in a dose of 15 or 20 mg. Stented patients randomized to placebo also received ticlopidine 250 mg orally BID for 4 weeks. Patients who received abciximab during the coronary intervention and who were randomized to receive xemilofiban were administered a reduced dosage (10 mg TID for 2 weeks) followed by the randomized maintenance dose of 15 or 20 mg BID for 2 more weeks. All patients received 325 mg aspirin PO QD. Ex vivo platelet aggregation in response to 20 micromol/L ADP and 4 microg/mL collagen was measured over time after the initial dose of study drug and at days 14 and 28 of long-term therapy in 230 patients. All patients were followed clinically for 90 days. Xemilofiban inhibited platelet aggregation to both ADP and collagen with peak levels of inhibition that were similar at 14 and 28 days of long-term oral therapy. Plasma levels of xemilofiban correlated with the degree of platelet inhibition. Peak platelet inhibition on day 1 correlated with the subsequent occurrence of insignificant or mild bleeding events. Although this study was not powered to evaluate differences in clinical outcomes, a trend (P=0.04) was observed for reduction of cardiovascular events at 3 months in patients not treated with abciximab who received the highest dose (20 mg) of xemilofiban studied. CONCLUSIONS: Xemilofiban inhibited platelet aggregation and was well tolerated during 28 days of long-term oral therapy. The observed trend in reduction of cardiovascular events in follow-up awaits confirmation in the larger-scale phase III study (EXCITE trial) currently in progress.

Administration, Oral↗

Application of random effect ordinal regression model for outcome evaluation of two randomized controlled trials.

Cluster randomization is often used in intervention trials, yet when individuals nested within clusters are considered as the units of analysis for outcome evaluation, it cannot be assumed that the observations are statistically independent. Observations that are not statistically independent also result when repeated measures are taken over time for the same individual. Ignoring clustered observations when performing data analysis can lead to the erroneous conclusion that the intervention under study had a statistically significant effect. Moreover, individual responses are often collected on ordinal scales; thus models for continuous or categorical data are usually not appropriate. We applied a random effect ordinal regression model to data sets from two randomized controlled intervention trials that measured graded scale non-independent responses. The first trial compared two school programmes for AIDS prevention in terms of impact (i.e., changes in the frequency of condom use). The second trial used the MOS-HIV questionnaire to measure the quality of life of new AIDS cases four times over a one-year follow-up period (only results of the role-functioning scale are reported). Regarding the first data set, the effect of the intervention was not significant, and the post-intervention frequency of condom use was mainly attributable to the pre-intervention frequency (p<0.01), with no differences among schools. Regarding the second data set, a borderline significant increase in the role-functioning scale scores was observed over the follow-up period; the results differed only slightly by intervention group; a significant (p<0.01) intra-individual correlation of 0.4 was found.

Acquired Immunodeficiency Syndrome↗

Nutritional therapy for peripheral arterial disease: a double-blind, placebo-controlled, randomized trial of HeartBar.

We investigated the clinical effects of a food bar enriched with L-arginine and a combination of other nutrients known to enhance the activity of endothelium-derived nitric oxide (EDNO) in individuals with claudication from atherosclerotic peripheral arterial disease. The study was a 2-week, double-blind, placebo-controlled trial of subjects randomized to three groups (two active bars, one active and one placebo bar, and two placebo bars per day) followed by an 8-week open-label period. Subjects (n=41) were outpatient volunteers with intermittent claudication. Pain-free and total walking distances were measured by variable-grade, treadmill exercise testing. Quality of life was assessed using the Medical Outcome Survey (SF-36). After 2 weeks of treatment, the pain-free walking distance increased 66% while the total walking distance increased 23% in the group taking two active bars/day. The general and emotional/social functioning components of the SF-36 also improved. These effects were not observed in the one active bar/day and placebo groups. The effects were maintained after 10 weeks and, in addition, an improvement in walking distance was observed in the group taking one active bar. These findings reveal that use of a nutrient bar designed to enhance EDNO activity improves pain-free and total walking distance as well as quality of life in individuals with intermittent claudication.

Aged↗

[Effectiveness of synthetic antioxidants in treatment of patients with peptic ulcer (an open randomized controlled trial)].

Two randomized groups of ulcer patients were compared. 102 patients of group 1 were treated with synthetic antioxidants (dibunol, probucol, emoxipine), while 100 patients of group 2 received a conventional treatment. Treatment results in group 1 appeared better: shortening of ulcer scarring, higher percentage of ulcer healing for 2 and 4 weeks, fall in the number of relapses during the first year of the follow-up, improvement in lipid peroxidation and antioxidant activity.

Adult↗

Angiotensin-converting enzyme inhibitors in patients with coronary artery disease and absence of heart failure or left ventricular systolic dysfunction: an overview of long-term randomized controlled trials.

BACKGROUND: Results of randomized trials of angiotensin-converting enzyme inhibitors in patients with coronary artery disease (CAD) and preserved left ventricular function are conflicting. We undertook this study to determine whether long-term prescription of angiotensin-converting enzyme inhibitors decreases major cardiovascular events and mortality in patients who have CAD and no evidence of left ventricular systolic dysfunction. METHODS: We searched MEDLINE, EMBASE, and IPA databases, the Cochrane Controlled Trials Register (1990-2004), and reports from scientific meetings (2003-2004), and we reviewed secondary sources. Search terms included angiotensin-converting enzyme inhibitors, coronary artery disease, randomi(s)zed controlled trials, clinical trials, and myocardial infarction. Eligible studies included randomized controlled trials in patients who had CAD and no heart failure or left ventricular dysfunction, with follow-up omicronf 2 years or longer. Of 1146 publications screened, 7 met our selection criteria and included a total of 33 960 patients followed up for a mean of 4.4 years. RESULTS: Five trials included only patients with documented CAD. One trial included patients with documented CAD (80%) or patients who had diabetes mellitus and 1 or more additional risk factors, and another trial included patients who had CAD, a history of transient ischemic attack, or intermittent claudication. Treatment with angiotensin-converting enzyme inhibitors decreased overall mortality (odds ratio, 0.86; 95% confidence interval, 0.79-0.93), cardiovascular mortality (odds ratio, 0.81; 95% confidence interval, 0.73-0.90), myocardial infarction (odds ratio, 0.82; 95% confidence interval, 0.75-0.89), and stroke (odds ratio, 0.77; 95% confidence interval, 0.66-0.88). Other end points, including resuscitation after cardiac arrest, myocardial revascularization, and hospitalization because of heart failure, were also reduced. CONCLUSION: Angiotensin-converting enzyme inhibitors reduce total mortality and major cardiovascular end points in patients who have CAD and no left ventricular systolic dysfunction or heart failure.

Aged↗

Randomized controlled trials in urologic oncology: a demographic analysis.

We examined randomized controlled trials in urologic oncology published in 1992. Particular emphasis was placed on the contribution of urologists and studies with a surgical arm. Randomized controlled trials in bladder, prostate, testis and renal carcinoma were identified by a structured MEDLINE search. Results were analyzed to determine modality of treatment, disease site, principal author, country of origin, cohort size, number of participating centers, source of funding and type of journal. MEDLINE retrieved 162 references of which 126 were excluded by title (10), abstracts (105) or articles (11) as not urologic oncology (7) or not a randomized controlled trials (119). Of the qualifying 36 randomized controlled trials, the site of the disease was bladder (44%), prostate (39%) renal (14%) and testis (3%). All except six randomized controlled trials compared medical therapies. Only five had a surgical arm and one had a radiation arm. Cohort size was > 100 in 67% of randomized controlled trials with most (56%) being multicenter trials. Participating countries were Europe, excluding the UK (35%), the US (23%), Japan (20%), Canada (13%), and the UK (10%). Urologists were the principal authors of 67% of the papers describing randomized controlled trials. The majority of trials were published in nonsurgical journals (50%). Funding for randomized controlled trials was from government (28%), pharmaceutical companies (19%), private sources (3%) and not stated (50%). Although randomized controlled trials are being conducted in urologic oncology, there are relatively few compared with trials using inferior study designs. A still smaller proportion of randomized controlled trials contain a surgical arm.

Journal Article↗

Rationale and design of the avoiding cardiovascular events through combination therapy in patients living with systolic hypertension (ACCOMPLISH) trial: the first randomized controlled trial to compare the clinical outcome effects of first-line combination therapies in hypertension.

Reducing blood pressure (BP) to target levels is a major priority in preventing clinical events in hypertension. Typically this requires more than one drug, and recent guidelines on hypertension management therefore recommend starting with combination treatment in many patients. Diuretics have often been part of such therapy, usually paired with angiotensin converting enzyme (ACE) inhibitors or similar agents; but calcium channel blockers are also highly efficacious in reducing BP when combined with ACE inhibitors. In addition, these drug classes, separately and in combination, appear to have vasculoprotective properties. Because the primary goal of treating hypertension is to enhance survival and reduce cardiovascular outcomes, the Rationale and Design of Avoiding Cardiovascular events through COMbination therapy in Patients LIving with Systolic Hypertension (ACCOMPLISH) trial is designed as the first blinded and randomized study to prospectively compare the effects on these endpoints of two antihypertensive combinations, benazapril/hydrochlorothiazide (force titrated to 40/12.5 mg) and amlodipine besylate/benazapril (force titrated to 5/40 mg). The doses can be further titrated to 40/25 mg or 10/40 mg, and other classes of drugs can be added as needed for optimal BP control. The primary study endpoint is a composite of cardiovascular mortality and morbidity. The study will be performed in hypertensive patients (systolic BP > or = 160 mm Hg or currently on antihypertensive therapy) with risk factors for cardiovascular events (prior events, target organ damage, kidney disease, or diabetes). A total of 6300 subjects will be randomized to each group with the expectation that a total of 1642 primary endpoints will occur during a 5-year period, providing 90% power to detect the 15% relative reduction in events (alpha = 0.05) hypothesized to favor the amlodipine besylate/benazapril group. The ACCOMPLISH study will be performed in the United States and Europe. The first patient was randomizedduring 2003, and the trial should conclude in 2008.

Antihypertensive Agents↗

Improving the quality of randomized controlled trials in Chinese herbal medicine, part III: quality control of Chinese herbal medicine used in randomized controlled trials.

OBJECTIVE: To discuss quality control of Chinese herbal medicine (CHM) in randomized controlled trials (RCTs), and to provide suggestions for improving this aspect in future clinical study in this therapeutic area. METHODS: A search of the Cochrane Library was conducted to identify RCTs of CHM. Quality control information reported in those RCTs was then assessed independently. RESULTS: The search yielded a total of 167 RCTs of CHM for a variety of conditions. A total of 11 CHM preparations were used in those RCTs. Only one trial discussed quality control of the CHM interventions used. Issues affecting the safety and efficacy of CHM products used in RCTs were discussed including standardization of raw herbal materials, processing methods, screening for product contamination, and effects of combination products. CONCLUSION: The overall quality of reporting of RCTs of CHM was poor, reflecting the need for improvements in reporting future clinical trials in this area. RECOMMENDATIONS: To improve quality control of CHM used in RCTs in future, we recommend developing and implementing guidelines such as Good Agricultural Practice (GAP) for Chinese crude drugs, and current Good Manufacturing Practice (GMP) specific to CHM products. Chemical analyses of individual herbs of CHM and combination products are also recommended to provide reference standards for quality control.

Drugs, Chinese Herbal↗

Colony-stimulating factors for chemotherapy-induced febrile neutropenia: a meta-analysis of randomized controlled trials.

PURPOSE: Current treatment for febrile neutropenia (FN) includes hospitalization for evaluation, empiric broad-spectrum antibiotics, and other supportive care. Clinical trials have reported conflicting results when studying whether the colony-stimulating factors (CSFs) improve outcomes in patients with FN. This Cochrane Collaboration review was undertaken to further evaluate the safety and efficacy of the CSFs in patients with FN. METHODS: An exhaustive literature search was undertaken including major electronic databases (CANCERLIT, EMBASE, LILACS, MEDLINE, SCI, and the Cochrane Controlled Trials Register). All randomized controlled trials that compare CSFs plus antibiotics versus antibiotics alone for the treatment of established FN in adults and children were sought. A meta-analysis of the selected studies was performed. RESULTS: More than 8,000 references were screened, with 13 studies meeting eligibility criteria for inclusion. The overall mortality was not influenced significantly by the use of CSF (odds ratio [OR] = 0.68; 95% CI, 0.43 to 1.08; P = .1). A marginally significant result was obtained for the use of CSF in reducing infection-related mortality (OR = 0.51; 95% CI, 0.26 to 1.00; P = .05). Patients treated with CSFs had a shorter length of hospitalization (hazard ratio [HR] = 0.63; 95% CI, 0.49 to 0.82; P = .0006) and a shorter time to neutrophil recovery (HR = 0.32; 95% CI, 0.23 to 0.46; P < .00001). CONCLUSION: The use of the CSFs in patients with established FN caused by cancer chemotherapy reduces the amount of time spent in hospital and the neutrophil recovery period. The possible influence of the CSFs on infection-related mortality requires further investigation.

Antineoplastic Agents↗

Thrombolysis compared with heparin for the initial treatment of pulmonary embolism: a meta-analysis of the randomized controlled trials.

BACKGROUND: Randomized trials and meta-analyses have reached conflicting conclusions about the role of thrombolytic therapy for the treatment of acute pulmonary embolism. METHODS AND RESULTS: We performed a meta-analysis of all randomized trials comparing thrombolytic therapy with heparin in patients with acute pulmonary embolism. Eleven trials, involving 748 patients, were included. Compared with heparin, thrombolytic therapy was associated with a nonsignificant reduction in recurrent pulmonary embolism or death (6.7% versus 9.6%; OR 0.67, 95% CI 0.40 to 1.12, P for heterogeneity=0.48), a nonsignificant increase in major bleeding (9.1% versus 6.1%; OR 1.42, 95% CI 0.81 to 2.46), and a significant increase in nonmajor bleeding (22.7% versus 10.0%; OR 2.63, 95% CI 1.53 to 4.54; number needed to harm=8). Thrombolytic therapy compared with heparin was associated with a significant reduction in recurrent pulmonary embolism or death in trials that also enrolled patients with major (hemodynamically unstable) pulmonary embolism (9.4% versus 19.0%; OR 0.45, 95% CI 0.22 to 0.92; number needed to treat=10) but not in trials that excluded these patients (5.3% versus 4.8%; OR 1.07, 95% CI 0.50 to 2.30), with significant heterogeneity between these 2 groups of trials (P=0.10). CONCLUSIONS: Currently available data provide no evidence for a benefit of thrombolytic therapy compared with heparin for the initial treatment of unselected patients with acute pulmonary embolism. A benefit is suggested in those at highest risk of recurrence or death. The number of patients enrolled in randomized trials to date is modest, and further evaluation of the efficacy and safety of thrombolytic therapy for the treatment of high-risk patients with acute pulmonary embolism appears warranted.

Acute Disease↗

Optimizing glycoprotein IIb/IIIa inhibition: lessons from recent randomized controlled trials.

Recent randomized clinical trials with intravenous glycoprotein IIb/IIIa inhibition have provided unanticipated results, thereby questioning their role as empirical medical management for acute coronary syndromes. The lack of benefit with abciximab observed in Global Utilization of Strategies to Open Occluded Coronary Arteries IV is somewhat inconsistent with the benefits seen with this agent in coronary intervention, and the benefits of an early invasive approach incorporating tirofiban seen within Treat Angina with Aggrastat and determine Cost of Therapy with an Invasive or Conservative Strategy Thrombolysis in Myocardial Infraction 18. Additionally, a direct 'head-to-head' comparative study of abciximab and tirofiban within the setting of percutaneous coronary intervention demonstrates clinically relevant superiority with abciximab with respect to 30-day outcomes. in the setting of coronary instability and mechanical plaque disruption is more complex than initially perceived. Hence, although an abundance of evidence details the efficacy of these agents, their optimal clinical application remains somewhat challenging in light of these recent data. However, within the context of previous trial experience, the current evidence highlights several key aspects of glycoprotein IIb/IIIa inhibitor therapy that may be associated with improved patient outcomes. In particular, these trials indicate: (i) the importance of selecting high-risk patients in whom substantial clinical benefit is evident, (ii) the incorporation of these agents into an early invasive strategy, thereby matching the timing of vascular injury with maximal platelet inhibition and (iii) optimal dosing to achieve the high levels of platelet inhibition that appear to be required for efficacy with these agents.

Abciximab↗

The Diabetes Manual trial protocol - a cluster randomized controlled trial of a self-management intervention for type 2 diabetes [ISRCTN06315411].

BACKGROUND: The Diabetes Manual is a type 2 diabetes self-management programme based upon the clinically effective 'Heart Manual'. The 12 week programme is a complex intervention theoretically underpinned by self-efficacy theory. It is a one to one intervention meeting United Kingdom requirements for structured diabetes-education and is delivered within routine primary care. METHODS/DESIGN: In a two-group cluster randomized controlled trial, GP practices are allocated by computer minimisation to an intervention group or a six-month deferred intervention group. We aim to recruit 250 participants from 50 practices across central England. Eligibility criteria are adults able to undertake the programme with type 2 diabetes, not taking insulin, with HbA1c over 8% (first 12 months) and following an agreed protocol change over 7% (months 13 to 18). Following randomisation, intervention nurses receive two-day training and delivered the Diabetes Manual programme to participants. Deferred intervention nurses receive the training following six-month follow-up. Primary outcome is HbA1c with total and HDL cholesterol; blood pressure, body mass index; self-efficacy and quality of life as additional outcomes. Primary analysis is between-group HbA1c differences at 6 months powered to give 80% power to detect a difference in HbA1c of 0.6%. A 12 month cohort analysis will assess maintenance of effect and assess relationship between self-efficacy and outcomes, and a qualitative study is running alongside. DISCUSSION: This trial incorporates educational and psychological diabetes interventions into a single programme and assesses both clinical and psychosocial outcomes. The trial will increase our understanding of intervention transferability between conditions, those diabetes related health behaviours that are more or less susceptible to change through efficacy enhancing mechanisms and how this impacts on clinical outcomes.

Adult↗

Are missing outcome data adequately handled? A review of published randomized controlled trials in major medical journals.

BACKGROUND: Randomized controlled trials almost always have some individuals with missing outcomes. Inadequate handling of these missing data in the analysis can cause substantial bias in the treatment effect estimates. We examine how missing outcome data are handled in randomized controlled trials in order to assess whether adequate steps have been taken to reduce nonresponse bias and to identify ways to improve procedures for missing data. METHODS: We reviewed all randomized trials published between July and December 2001 in BMJ, JAMA, Lancet and New England Journal of Medicine, excluding trials in which the primary outcome was described as a time-to-event. We focused on trial designs, how missing outcome data were described and the statistical methods used to deal with the missing outcome data, including sensitivity analyses. RESULTS: We identified 71 trials of which 63 (89%) reported having partly missing outcome data: 13 trials had more than 20% of patients with missing outcomes. In 26 trials that measured the outcome at a single time point, 92% performed a complete case analysis and 8% imputed the missing outcomes using baseline values or the worst case value. In 37 trials with repeated measures of the outcome, 46% performed complete case analyses, potentially excluding individuals with some follow-up data, while 14% performed a repeated measures analysis, 19% used the last observation carried forward, 11% imputed with the worst case value and 2% imputed using regression predictions. Thirteen (21%) of trials with missing data reported a sensitivity analysis. CONCLUSIONS: Our review shows that missing outcome data are a common problem in randomized controlled trials, and are often inadequately handled in the statistical analysis in the top tier medical journals. Authors should explicitly state the assumptions underlying the handling of the missing outcomes and justify them through data descriptions and sensitivity analyses.

Bias↗