Abandoned trials are unpublished trials that sponsors are no longer actively working to publish or published trials that, although documented as misreported, have not been corrected by the authors.
The findings from the present trial are consistent with these previous DCB proof-of-concept trials that, although smaller because they were powered on a 6-month angiographic end point, enrolled a similar patient population with symptomatic femoropopliteal disease.
Such trials might be systematically different from trials that were included, although the variation observed in this study is unlikely to be affected by the inclusion of a small number of additional trials.
Both centers Emory Winship Cancer Institute in Atlanta and the Carle Cancer Center in Urbana, Illinois have stopped enrolling new patients into clinical trials, although trials that are already up and running can continue with volunteers who signed on earlier.
Furthermore, participation in a Phase 0 trial might delay or exclude the patient from other clinical trials that may have some, although little, therapeutic intent.
To-date trial evidence supports the recommendation to lower systolic BP below 140 mmHg in grade I uncomplicated low cardiovascular risk hypertensive patients, based on the fact that in most trials that involved these patients (although often their "uncomplicated low-risk hypertension category" was questionable [ 4]), a reduction in cardiovascular events was associated with systolic BP <140 mmHg.
Carefully planned and well-executed RCTs give us the best estimates of treatment effect and can thus guide clinical decision making [ 2, 3], although trials that lack methodological rigor cause over- or underestimation of treatment effect sizes due to bias [ 4- 6].
It is possible that our search did not identify all randomized clinical trials that have examined this issue, although our extensive search using multiple databases, use of multiple search terms, and contact with industry make this unlikely.
We did not identify any trials that specifically assessed pharmacological interventions, although among the three identified ongoing trials not included in this review, one European trial assesses the efficacy and safety of smoking cessation with varenicline tartrate in patients with diabetes.
Although the trials that have investigated the use of hyaluronan therapy for the management of traumatic and degenerative musculoskeletal disorders seen in sports medicine have limitations in design and patient number, the results have been promising and suggest that larger controlled clinical trials are warranted (Peyron and Balasz 1974).
The reduction of inflammation in COPD may reduce the increased risk of CVD and lung cancer that occurs in this context, although the clinical trials that have addressed this issue are very limited.
