Authentication Systems for Securing Clinical Documentation Workflows

SummaryContext: Integration of electronic signatures embedded in health care processes in Germany challenges health care service and supply facilities. The suitability of the signature level of an eligible authentication procedure is confirmed for a large part of documents in clinical practice. However, the concrete design of such a procedure remains unclear.Objective: To create a summary of usable user authentication systems suitable for clinical workflows.Data Source: A Systematic literature review based on nine online bibliographic databases. Search Keywords included authentication, access control, information systems, information security and biometrics with terms user authentication, user identification and login in title or abstract. Searches were run between 7 and 12 September 2011. Relevant conference proceedings were searched manually in February 2013. Backward reference search of selected results was done.Selection: Only publications fully describing authentication systems used or usable were included. Algorithms or purely theoretical concepts were excluded. Three authors did selection independently.Data Extraction and Assessment: Semi-structured extraction of system characteristics was done by the main author. Identified procedures were assessed for security and fulfillment of relevant laws and guidelines as well as for applicability. Suitability for clinical workflows was derived from the assessments using a weighted sum proposed by Bonneau.Results: Of 7575 citations retrieved, 55 publications meet our inclusion criteria. They describe 48 different authentication systems; 39 were biometric and nine graphical password systems. Assessment of authentication systems showed high error rates above European CENELEC standards and a lack of ap -plicability of biometric systems. Graphical passwords did not add overall value compared to conventional passwords. Continuous authentication can add an additional layer of safety. Only few systems are suitable partially or entirely for use in clinical processes.Conclusions: Suitability strongly depends on national or institutional requirements. Four authentication systems seem to fulfill requirements of authentication procedures for clinical workflows. Research is needed in the area of continuous authentication with biometric methods. A proper authentication system should combine all factors of au -thentication implementing and connecting secure individual measures.</jats:p

A new metric enabling an exact hypergraph model for the communication volume in distributed-memory parallel applications

A hypergraph model for mapping applications with an all-neighbor communication pattern to distributed-memory computers is proposed, which originated in finite element triangulations. Rather than approximating the communication volume for linear algebra operations, this new model represents the communication volume exactly. To this end, a hypergraph partitioning problem is formulated where the objective function involves a new metric. This metric, the kðk 1Þ-metric, accurately models the communication volume for an all-neighbor communication pattern occurring in a concrete finite element application. It is a member of a more general class of metrics, which also contains more widely used metrics, such as the cut–net and the ðk 1Þ-metric. In addition, we develop a heuristic to minimize the communication volume in the new kðk 1Þ-metric. For the solution of several real-world finite element problems, experimental results based on this new heuristic demonstrate a small reduction in communication volume compared to a standard graph partitioner and do not show significant reductions in communication volume compared to a hypergraph partitioner using the common ðk 1Þ-metric. However, for this set of problems, the new approach does reduce actual communication times. As a by-product, we observe that it also tends to reduce the number of messages. Furthermore, the new approach dramatically reduces the communication volume for a set of sparse matrix problems that are more irregularly-structured than finite element problems

Influence of mounting on the optical surface figure in optical reference surfaces

The paper presents the effect of mechanical mounting of optical reference elements on their surface shape. Optical reference surfaces are key elements when traceable, highly accurate and precise optical surface measurements are required. In order to calibrate measuring instruments and compare the metrological capabilities of different metrology institutes, universities and other stakeholders, the reference artefacts were developed. Different measurement instruments require a different way of mounting and the reference artefacts are supposed to be useful for reliable and repeatable calibration of a great majority of the instruments worldwide. However, not only their shape was critical, but also the way of mounting was crucial. FEM analyses followed by experiments have revealed an unacceptable surface shape error in the order of hundreds of nanometres in the case of the commonly used screw mount, even for low applied torques. Other mounting options, such as the collet chuck or the Morse taper, are examined by means of FEM analysis and verified by interferometric measurements. It is shown that only the Morse taper can fulfil the strict criterion of less than 30 nm for surface shape deviation due to mounting, which is required in optical surface shape metrology.</jats:p

Altlastenbericht 1. Fortschreibung

With 1 mapTIB Hannover RO 8421(1989,1) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Predicting procedural success in patients treated with Cardioband system for severe tricuspid regurgitation by employing a random forest algorithm

Abstract Background Severe tricuspid regurgitation (TR) is associated with high morbidity and mortality despite optimal medical treatment. Transcatheter tricuspid valve intervention (TTVI) is therefore emerging as a novel treatment option, fueling the hope to prolong survival and reduce rehospitalization for heart failure. Obviously, procedural success of TTVI is an important determinant of survival, but predictors for procedural success in patients treated with Cardioband system, which mimics the surgical approach by implanting an annular reduction system and hence targets tricuspid annulus dilatation as the central pathology in most patients, are largely elusive. Purpose This study aims to refine prediction of procedural success in patients with severe TR undergoing TTVI with Cardioband system by employing a random forest algorithm. Methods Procedural success was evaluated in 72 patients enrolled at two tertiary centers in Germany between 2018 and 2020. Key inclusion criterion was TR ≥ III/V° with high symptomatic burden despite optimal medical treatment. Procedural success war defined as patient alive at the end of the procedure, successful Cardioband implantation, and TR reduction ≥ II/V° as assessed on transthoracic echocardiography before discharge. Since 66.7% of patients were classified as “success”, a synthetic minority over-sampling technique was applied in order to train the random forest algorithm on a balanced data set. Results A random forest algorithm reached 85.4% accuracy (AUC: 0.923) in predicting procedural success in a balanced data set using eight parameters from pre-procedural echocardiography as input variables. Partial dependence analysis revealed that enlargement of the tricuspid valve (TV) anteroseptal diameter was most important for model accuracy. Applied to the real-world data set (24 patients classified as “failure” and 48 patients classified as “success”), the now trained random forest algorithm predicted procedural success with high sensitivity (70.8%) and specificity (100.0%), significantly outperforming the no information rate (p-value: 0.0069). Patients with low probability for success were characterized by impaired right ventricular function (TAPSE: 15.5±3.63 mm) and enlarged right sided cardiac diameters (basal right ventricular diameter: 51.6±3.79 mm; TV anteroseptal diameter: 45.0±5.10 mm). Notably, systolic pulmonary artery pressure (sPAP) and TV effective regurgitant orifice area were negatively correlated (R: −0.3004, p-value: 0.0322), and elevation in sPAP was attenuated in patients with low probability for procedural success (sPAP: 34.0±11.7 mmHg). Conclusion A random forest algorithm enables precise prediction of procedural success in patients treated with Cardioband system. TR reduction ≥ II/V° appears less achievable in patients with advanced stages of right heart failure, emphasizing the importance of adequate patient selection and timing of intervention. Funding Acknowledgement Type of funding sources: None. </jats:sec

Congestion patterns in severe tricuspid regurgitation and transcatheter treatment: Insights from a multicentre registry.

AIMS While invasively determined congestion holds mechanistic and prognostic significance in acute heart failure (HF), its role in patients with tricuspid regurgitation (TR)-related right- heart failure (HF) undergoing transcatheter tricuspid valve intervention (TTVI) is less well established. A comprehensive understanding of congestion patterns might aid in procedural planning, risk stratification, and the identification of patients who may benefit from adjunctive therapies before undergoing TTVI. The aim of this study was to investigate the role of congestion patterns in patients with severe TR and its implications for TTVI. METHODS AND RESULTS Within a multicentre, international TTVI registry, 813 patients underwent right heart catheterization (RHC) prior to TTVI and were followed up to 24 months. The median age was 80 (interquartile range 76-83) years and 54% were women. Both mean right atrial pressure (RAP) and pulmonary capillary wedge pressure (PCWP) were associated with 2-year mortality on Cox regression analyses with Youden index-derived cut-offs of 17 mmHg and 19 mmHg, respectively (p < 0.01 for all). However, RAP emerged as an independent predictor of outcomes following multivariable adjustments. Pre-interventionally, 42% of patients were classified as euvolaemic (RAP <17 mmHg, PCWP <19 mmHg), 23% as having left-sided congestion (RAP <17 mmHg, PCWP ≥19 mmHg), 8% as right-sided congestion (RAP ≥17 mmHg, PCWP <19 mmHg), and 27% as bilateral congestion (RAP ≥17 mmHg, PCWP ≥19 mmHg). Patients with right-sided or bilateral congestion had the lowest procedural success rates and shortest survival times. Congestion patterns allowed for discerning specific patient's physiology and specifying prognostic implications of right ventricular to pulmonary artery coupling surrogates. CONCLUSION In this large cohort of invasively characterized patients undergoing TTVI, congestion patterns involving right-sided congestion were associated with low procedural success and higher mortality rates after TTVI. Whether pre-interventional reduction of right-sided congestion can improve outcomes after TTVI should be established in dedicated studies