Cognitive error analysis in accident and incident investigation in safety-critical domains

A database of 10 years' worth of medical incident data gathered in an Edinburgh Intensive Care Unit was analyzed using the proposed cognitive error analysis approach. In the second live case study, the error analysis approach was evaluated in the field by applying it to incident reporting data that was collected with a newly implemented incident reporting scheme in a Glasgow Neonatal Intensive Care Unit. The insights gained by analyzing the Edinburgh incident scheme were used to inform the design and implementation of the Glasgow incident scheme as part of the unit's existing safety management. Since both were local incident reporting schemes, it was seen as an important factor for its success to take the local context and conditions into account while situating the cognitive error analysis approach as part of these hospitals' safety management strategies. The evaluation of this incident reporting and analysis framework demonstrated the benefits of a structured, psychological “human error” analysis approach that centres on the human aspect of the incident, without isolating it from its context. It is argued that not only could the understanding of the underlying error mechanisms be improved for individual incidents, but the generation of safety recommendations could be supported, and these could then also be evaluated as to their impact on the human "in the loop". The resulting error analysis models could further be used as basis for comparing competing analyses, and also improve analysis traceability by documenting the analysis process and its resulting safety recommendations. Further work is needed in providing "best practices" for the application of the cognitive analytical framework. Further work is also needed in formalizing a way to situate the cognitive error analysis approach within the investigation of local work system factors in the search for the overall incident and accident causation. This thesis aims at demonstrating the benefits of grounding the analysis of human error as part of incident and accident reporting in a cognitive theoretical framework. This will provide the means and the vocabulary to reason about alternative causal hypotheses while also acting as a tool to document and communicate the psychological analysis of human error and its resulting safety recommendations. This approach is proposed as complementing the analysis of human error data by means of error taxonomies grounded in psychological theory

Phase engineering in tantalum sulfide monolayers on Au(111)

We prepare monolayers of tantalum sulfide on Au(111) by evaporation of Ta in a reactive background of H$_2$S. Under sulfur-rich conditions, monolayers of 2H-TaS$_2$ develop, whereas under sulfur-poor conditions TaS forms, a structure that can be derived from 2H-TaS$_2$ by removal of the bottom S layer. We analyse the alignment of the layers with respect to the substrate and the relation with the domains in the Au(111) herringbone reconstruction using scanning tunneling microscopy (STM). With the help of density functional theory (DFT) calculations we can determine the registry of the two phases with the substrate. We develop a growth process that allows preparation of uniquely oriented 2H-TaS$_2$ on Au(111). 2H-TaS$_2$ and TaS have a remarkably similar in-plane lattice structure and we observe the formation of lateral 2H-TaS$_2$-TaS heterostructures with atomically well-defined and defect-free boundaries. We observe mirror twin boundaries within 2H-TaS$_2$ along the S- and Ta-edge

Perspectives on gender and product design

International audienceInteractive technologies have a profound mediating effect on the way we obtain and contribute to knowledge, relate to each other and contribute to society. Often, "gender" is not a factor that is explicitly considered in the design of these technologies. When gender is considered, products are often designed with idealised models of gendered "users" -- designed for men, designed for women, designed for boys, designed for girls, or designed for the "average user" who could be male or female. However, the ways in which gender-bias or gender-neutrality are constructed in the design process and the resulting effect on the interactive artifacts that are produced is not well understood. This workshop will address what HCI is currently bringing, and can bring, to the table in addressing this issue

Resonance Raman spectrum of doped epitaxial graphene at the Lifshitz transition

We employ ultra-high vacuum (UHV) Raman spectroscopy in tandem with angle-resolved photoemission (ARPES) to investigate the doping-dependent Raman spectrum of epitaxial graphene on Ir(111). The evolution of Raman spectra from pristine to heavily Cs doped graphene up to a carrier concentration of 4.4*10^14cm^-2 is investigated. At this doping graphene is at the onset of the Lifshitz transition and renormalization effects reduce the electronic bandwidth. The optical transition at the saddle point in the Brillouin zone then becomes experimentally accessible by ultraviolet (UV) light excitation which achieves resonance Raman conditions in close vicinity to the van Hove singularity in the joint density of states. The position of the Raman G band of fully doped graphene/Ir(111) shifts down by ~60cm^-1. The G band asymmetry of Cs doped epitaxial graphene assumes an unusual strong Fano asymmetry opposite to that of the G band of doped graphene on insulators. Our calculations can fully explain these observations by substrate dependent quantum interference effects in the scattering pathways for vibrational and electronic Raman scattering

Multimorbidity Patterns in the Elderly: A New Approach of Disease Clustering Identifies Complex Interrelations between Chronic Conditions

Objective: Multimorbidity is a common problem in the elderly that is significantly associated with higher mortality, increased disability and functional decline. Information about interactions of chronic diseases can help to facilitate diagnosis, amend prevention and enhance the patients ’ quality of life. The aim of this study was to increase the knowledge of specific processes of multimorbidity in an unselected elderly population by identifying patterns of statistically significantly associated comorbidity. Methods: Multimorbidity patterns were identified by exploratory tetrachoric factor analysis based on claims data of 63,104 males and 86,176 females in the age group 65+. Analyses were based on 46 diagnosis groups incorporating all ICD-10 diagnoses of chronic diseases with a prevalence $ 1%. Both genders were analyzed separately. Persons were assigned to multimorbidity patterns if they had at least three diagnosis groups with a factor loading of 0.25 on the corresponding pattern. Results: Three multimorbidity patterns were found: 1) cardiovascular/metabolic disorders [prevalence female: 30%; male: 39%], 2) anxiety/depression/somatoform disorders and pain [34%; 22%], and 3) neuropsychiatric disorders [6%; 0.8%]. The sampling adequacy was meritorious (Kaiser-Meyer-Olkin measure: 0.85 and 0.84, respectively) and the factors explained a large part of the variance (cumulative percent: 78 % and 75%, respectively). The patterns were largely age-dependent an

IGLV3-21*01 is an inherited risk factor for CLL through the acquisition of a single-point mutation enabling autonomous BCR signaling

The prognosis of chronic lymphocytic leukemia (CLL) depends on different markers, including cytogenetic aberrations, oncogenic mutations, and mutational status of the immunoglobulin (Ig) heavy-chain variable (IGHV) gene. The number of IGHV mutations distinguishes mutated (M) CLL with a markedly superior prognosis from unmutated (UM) CLL cases. In addition, B cell antigen receptor (BCR) stereotypes as defined by IGHV usage and complementarity-determining regions (CDRs) classify ∼30% of CLL cases into prognostically important subsets. Subset 2 expresses a BCR with the combination of IGHV3-21-derived heavy chains (HCs) with IGLV3-21-derived light chains (LCs), and is associated with an unfavorable prognosis. Importantly, the subset 2 LC carries a single-point mutation, termed R110, at the junction between the variable and constant LC regions. By analyzing 4 independent clinical cohorts through BCR sequencing and by immunophenotyping with antibodies specifically recognizing wild-type IGLV3-21 and R110-mutated IGLV3-21 (IGLV3-21R110), we show that IGLV3-21R110-expressing CLL represents a distinct subset with poor prognosis independent of IGHV mutations. Compared with other alleles, only IGLV3-21*01 facilitates effective homotypic BCR-BCR interaction that results in autonomous, oncogenic BCR signaling after acquiring R110 as a single-point mutation. Presumably, this mutation acts as a standalone driver that transforms IGLV3-21*01-expressing B cells to develop CLL. Thus, we propose to expand the conventional definition of CLL subset 2 to subset 2L by including all IGLV3-21R110-expressing CLL cases regardless of IGHV mutational status. Moreover, the generation of monoclonal antibodies recognizing IGLV3-21 or mutated IGLV3-21R110 facilitates the recognition of B cells carrying this mutation in CLL patients or healthy donors

Specialist involvement and referral patterns in ambulatory medical care for patients with dementia in Germany: results of a claims data based case-control study

<p>Abstract</p> <p>Background</p> <p>To analyze the referral processes from general practitioners to specialists and among specialists for dementia patients in the time periods before, during and after the diagnosis in Germany.</p> <p>Methods</p> <p>In this case-control study claims data from 1,848 insurants with incident dementia aged 65 years and more and 7,392 matched controls were compared over a two-year period covering the pre-incidence, incidence and post-incidence time periods.</p> <p>Results</p> <p>We found an increase in referrals of 30% in the incidence quarter, mainly from general practice to neuropsychiatry and from there to radiology. Referrals to clinical chemistry and other disciplines for dementia-specific reasons were negligible in amount. 34% of incident cases had at least one contact with a neuropsychiatrist during the year of incidence, and the majority of them visited this specialist repeatedly during that year. Only a minority (13.5%) of patients was referred to radiology for imaging. Referrals to other specialists declined whereas self-referrals did not increase.</p> <p>Conclusions</p> <p>The referral rates to relevant specialists (neuropsychiatry, radiology and clinical chemistry) are far less frequent than proposed in German guidelines. More research is needed to explain the gape between guidelines and daily care and to find ways for a better implementation of guidelines in ambulatory care. Guidelines should not only deal with diagnostic procedures and therapeutic options but also consider questions of applicability in daily clinical practice and propose effective organizational models of care provision.</p

Which chronic diseases and disease combinations are specific to multimorbidity in the elderly? Results of a claims data based cross-sectional study in Germany

<p>Abstract</p> <p>Background</p> <p>Growing interest in multimorbidity is observable in industrialized countries. For Germany, the increasing attention still goes still hand in hand with a small number of studies on multimorbidity. The authors report the first results of a cross-sectional study on a large sample of policy holders (n = 123,224) of a statutory health insurance company operating nationwide. This is the first comprehensive study addressing multimorbidity on the basis of German claims data. The main research question was to find out which chronic diseases and disease combinations are specific to multimorbidity in the elderly.</p> <p>Methods</p> <p>The study is based on the claims data of all insured policy holders aged 65 and older (n = 123,224). Adjustment for age and gender was performed for the German population in 2004. A person was defined as multimorbid if she/he had at least 3 diagnoses out of a list of 46 chronic conditions in three or more quarters within the one-year observation period. Prevalences and risk-ratios were calculated for the multimorbid and non-multimorbid samples in order to identify diagnoses more specific to multimorbidity and to detect excess prevalences of multimorbidity patterns.</p> <p>Results</p> <p>62% of the sample was multimorbid. Women in general and patients receiving statutory nursing care due to disability are overrepresented in the multimorbid sample. Out of the possible 15,180 combinations of three chronic conditions, 15,024 (99%) were found in the database. Regardless of this wide variety of combinations, the most prevalent individual chronic conditions do also dominate the combinations: Triads of the six most prevalent individual chronic conditions (hypertension, lipid metabolism disorders, chronic low back pain, diabetes mellitus, osteoarthritis and chronic ischemic heart disease) span the disease spectrum of 42% of the multimorbid sample. Gender differences were minor. Observed-to-expected ratios were highest when purine/pyrimidine metabolism disorders/gout and osteoarthritis were part of the multimorbidity patterns.</p> <p>Conclusions</p> <p>The above list of dominating chronic conditions and their combinations could present a pragmatic start for the development of needed guidelines related to multimorbidity.</p