Comparison of open-source software for producing directed acyclic graphs.

Many software packages have been developed to assist researchers in drawing directed acyclic graphs (DAGs), each with unique functionality and usability. We examine five of the most common software to generate DAGs: TikZ, DAGitty, ggdag, dagR, and igraph. For each package, we provide a general description of its background, analysis and visualization capabilities, and user-friendliness. Additionally in order to compare packages, we produce two DAGs in each software, the first featuring a simple confounding structure, while the second includes a more complex structure with three confounders and a mediator. We provide recommendations for when to use each software depending on the user's needs.

Baseline Characteristics and Clinical Outcomes of a Tricuspid Regurgitation Referral Population.

Adverse outcomes in tricuspid regurgitation (TR) have been associated with advanced regurgitation severity and right-sided cardiac remodeling, and late referrals for tricuspid valve surgery in TR have been associated with increase in postoperative mortality. The purpose of this study was to evaluate baseline characteristics, clinical outcomes, and procedural utilization of a TR referral population. We analyzed patients with a diagnosis of TR referred to a large TR referral center between 2016 and 2020. We evaluated baseline characteristics stratified by TR severity and analyzed time-to-event outcomes for a composite of overall mortality or heart-failure hospitalization. In total, 408 patients were referred with a diagnosis of TR: the median age of the cohort was 79 years (interquartile range 70 to 84), and 56% were female. In patients evaluated on a 5-grade scale, 10.2% had ≤moderate TR; 30.7% had severe TR; 11.4% had massive TR, and 47.7% had torrential TR. Increasing TR severity was associated with right-sided cardiac remodeling and altered right ventricular hemodynamics. In multivariable Cox regression analysis, New York Heart Association class symptoms, history of heart failure hospitalization, and right atrial pressure were associated with the composite outcome. One-third of patients referred underwent transcatheter tricuspid valve intervention (19%) or surgery (14%); patients who underwent transcatheter tricuspid valve intervention had greater preoperative risk than that of patients who underwent surgery. In conclusion, in patients referred for evaluation of TR, there were high rates of massive and torrential regurgitation and advanced right ventricle remodeling. Symptoms and right atrial pressure are associated with clinical outcomes in follow-up. There were significant differences in baseline procedural risk and eventual therapeutic modality.

The accuracy benefit of multiple amperometric glucose sensors in people with type 1 diabetes.

OBJECTIVE: To improve glucose sensor accuracy in subjects with type 1 diabetes by using multiple sensors and to assess whether the benefit of redundancy is affected by intersensor distance. RESEARCH DESIGN AND METHODS: Nineteen adults with type 1 diabetes wore four Dexcom SEVEN PLUS subcutaneous glucose sensors during two 9-h studies. One pair of sensors was worn on each side of the abdomen, with each sensor pair placed at a predetermined distance apart and 20 cm away from the opposite pair. Arterialized venous blood glucose levels were measured every 15 min, and sensor glucose values were recorded every 5 min. Sensors were calibrated once at the beginning of the study. RESULTS: The use of four sensors significantly reduced very large errors compared with one sensor (0.4 vs. 2.6% of errors ≥50% from reference glucose, P < 0.001) and also improved overall accuracy (mean absolute relative difference, 11.6 vs. 14.8%, P < 0.001). Using only two sensors also significantly improved very large errors and accuracy. Intersensor distance did not affect the function of sensor pairs. CONCLUSIONS: Sensor accuracy is significantly improved with the use of multiple sensors compared with the use of a single sensor. The benefit of redundancy is present even when sensors are positioned very closely together (7 mm). These findings are relevant to the design of an artificial pancreas device.