Different Contexts Of Use Research Articles

Quantity over quality: Do single-item scales reflect what users truly experienced?

Single-item scales are widely used in the field of user experience to report the emotions. However, they are strongly criticized and discouraged by the scientific community. While they have several practical advantages, single-item scales are mainly criticized for their psychometric weakness. Our research explores to what extent single-item scales reflect what a user has experienced during his or her interaction with technology, overall, but also at specific moments such as first and last impressions. This research also explores the sensitivity of these measures across different contexts of use brought by the presence or absence of certain interface features. We conducted a correlational study with 40 users while interacting with financial institution websites. We used two methods to evaluate the experience: lived and measured implicitly using psychophysiological instruments on one hand and self-perceived and measured using single-item scales, on the other hand. Overall, our results suggest limited correlations and in most cases contradictory between lived and perceived experience. We conclude by highlighting the limits to be taken into account when professionals are led to use single-item scales.

Revision of the Wisconsin Smoking Withdrawal Scale: Development of brief and long forms.

The assessment of tobacco withdrawal is important for both research and clinical purposes. This study describes the psychometric development of a revised version of the 28-item Wisconsin Smoking Withdrawal Scale (WSWS; Welsch et al., Experimental and Clinical Psychopharmacology, 1999, 7, p. 354). Because the different contexts of use sometimes permit only brief assessment, this revision has produced both a brief and longer form using an updated pool of candidate items. For the revised Wisconsin Smoking Withdrawal Scale 2 (WSWS2), a candidate pool of 37 items was developed to measure nine putative withdrawal constructs. The stem and wording of items were revised as was the response scale. Data for psychometric analyses were derived from three smoking cessation randomized clinical trials conducted at the University of Wisconsin Center for Tobacco Research and Intervention. Dimensionality, internal consistency, and item characteristic analyses of the candidate items were conducted in a derivation sample to ascertain the factor structure and to identify items that could be used in the WSWS2 scales. Confirmatory factor analyses (CFAs) of reduced item sets and factor structure were conducted in two validation samples along with reliability and validity analyses. Derivation and validation sample analyses yielded a longer version of the WSWS2 (WSWS2-L) with 19 items and six subscales (Craving, Negative Affect, Hunger, Sleep, Restlessness, and Concentration) and a brief 6-item version (WSWS2-B). In validation sample analyses, both the WSWS2-L and the WSWS2-B demonstrated good reliability and validity as well as good fit in CFAs. The WSWS2-L and WSWS2-B possess improved construct coverage, fewer items, and other enhancements relative to the WSWS. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

QualDash: Adaptable Generation of Visualisation Dashboards for Healthcare Quality Improvement.

Adapting dashboard design to different contexts of use is an open question in visualisation research. Dashboard designers often seek to strike a balance between dashboard adaptability and ease-of-use, and in hospitals challenges arise from the vast diversity of key metrics, data models and users involved at different organizational levels. In this design study, we present QualDash, a dashboard generation engine that allows for the dynamic configuration and deployment of visualisation dashboards for healthcare quality improvement (QI). We present a rigorous task analysis based on interviews with healthcare professionals, a co-design workshop and a series of one-on-one meetings with front line analysts. From these activities we define a metric card metaphor as a unit of visual analysis in healthcare QI, using this concept as a building block for generating highly adaptable dashboards, and leading to the design of a Metric Specification Structure (MSS). Each MSS is a JSON structure which enables dashboard authors to concisely configure unit-specific variants of a metric card, while offloading common patterns that are shared across cards to be preset by the engine. We reflect on deploying and iterating the design of OualDash in cardiology wards and pediatric intensive care units of five NHS hospitals. Finally, we report evaluation results that demonstrate the adaptability, ease-of-use and usefulness of QualDash in a real-world scenario.

What is the Relation between Semantic and Substantive Epistemic Contextualism?

Epistemic Contextualism is generally treated as a semantic thesis that may or may not have epistemological consequences. It is sometimes taken to concern only knowledge claims (as the assertion that the word “know” means different things in different contexts of use). Still, at other times it is taken to regard the knowledge relation itself (as the assertion that knowledge itself has no single univocal nature). Call the former view Semantic EC, the latter view Substantive EC, and the idea that the plausibility of Semantic EC presupposes that of Substantive EC, the “Presupposition Thesis.” Numerous authors argue against the Presupposition Thesis on the grounds that an understanding of the nature of knowledge is no more required to understand the meaning of knowledge assertions than an understanding of the self, for instance, is needed to understand the meaning of sentences containing “I.” These authors then offer additional arguments for the same conclusion, using further comparisons between “know” and other indexicals, as well as between “know” and quantifiers, gradable and modal adjectives. Herein, I defend the Presupposition Thesis by arguing against these authors’ claims (based as they are on these types of comparisons) that Semantic EC is plausible without the supposition of Substantive EC.

Malacitana® y Malacitana Sans®: Las nuevas tipografías de la Universidad de Málaga

Este artículo analiza el contexto y el proceso de diseño del sistema tipográfico hecho a medida para la Universidad de Málaga: Malacitana®. “Malacitana®” y “Malacitana Sans®” componen un sistema tipográfico multilenguaje abierto, pensado para reforzar, en su uso, el sentimiento de pertenencia de la comunidad universitaria. “Malacitana” es el resultado de un proceso de investigación que parte del convencimiento del valor estratégico de sistema tipográfico propio como vehículo para dotar de un estilo característico el flujo de información y conocimiento que genera, y canaliza, una institución en la cultura como es la Universidad de Málaga.
 En este artículo, además, se detallan los rasgos estilísticos que caracterizan este proyecto tipográfico en el contexto de proyectos similares. "Malacitana®" es un tipo de letra con remates (slab-serif) diseñada sobre una estructura humanista. Malacitana Sans® es una tipografia lineal humanista (según la clasificación de VOX ATypI). Estas tipografías ofrecen un set de caracteres ampliado y una amplia cobertura lingüística (Latin Pro, Ext-A, Ext-B) que garantiza su aplicación en diferentes contextos de uso.

Unveiling Usability and UX Relationships for Different Gender, Users Habits and Contexts of Use

Despite the abundance of research into usability and user experience (UX), there are few works approaching how the context influences the relationships between these two concepts. The actual experience of a user highly depends on personal characteristics, like the social and cultural background. In this work, we address user-related and contextual factors for a better comprehension of usability UX correlations. We conducted a study with 160 participants in entertainment, e-bank, education and e-commerce websites. As a result, for both sex and usage time user classes, a good usability was positively correlated to positive emotions. Despite the correlations between usability and female users negative and positive emotional reactions are greater than for male users, no significant difference was observed. Also, there was no significant difference involving correlations between usability and emotional reactions, when comparing less and more frequent users. As another result, there are differences of the degree of the correlations between perceived usability and emotional responses in different contexts of use, when dividing the users on sex and usage time classes, but the correlations between usability and positive emotions remained positive. In spite of the particularities of user classes, similarities on the usability for different user classes and the agreement of patterns of correlations with previous literature, our results reinforces the usability as a determinant aspect for UX.

The British Library’s Scholarly Communications Toolkit

As a national library, the British Library aims to deliver valuable services to both individual researchers and other research institutions, including those recognised by UK Research and Innovation as ‘Independent Research Organisations’. The British Library’s Scholarly Communications Toolkit is a series of ‘quick start’ guides to important elements of scholarly communications, including open access, research data management, publishing, research impact, and copyright. While addressing internal needs, they have been developed to also meet the needs of external organisations that may not have in-house support for scholarly communications. Being openly licensed and published in multiple formats, they are easily adapted to different contexts of use. This poster outlines the British Library’s approach to supporting scholarly communications both internally and externally, and introduces the series of leaflets which will be publicly available by the date of the 2020 Munin Conference on Scholarly Publishing.

SNUXH: A Set of Social Network User Experience Heuristics

With the growth and overcrowding of the internet, the use of online social networks has been increasing. Currently, social networks are used by a wide variety of users–with different objectives and in different contexts of use–, so it is essential to design intuitive and easy to use social network applications that generate a positive user experience (UX). The heuristic evaluation is a well-known evaluation method that allows detecting usability problems; a group of experts evaluates a product and/or system using a set of heuristics as a guide. Although the heuristic evaluation is oriented to evaluate the usability, it can be useful to evaluate other aspects related to the UX. Due to the specific features of social networks, it is necessary to have a specific set of heuristics to evaluate them. Sets of specific heuristics for social networks have been proposed, but they focus on evaluating the only usability. This article presents a set of heuristics that attend not only usability issues, but other UX factors as well, social network user experience heuristics (SNUXH). The new set of heuristics was developed, validated, and refined in four iterations. The results obtained in the experimental validation indicate that the SNUXH set is useful and more effective than generic heuristics (Nielsen’s heuristics) when evaluating social networks.

An experimental investigation of menu selection for immersive virtual environments: fixed versus handheld menus

With the development of consumer-grade virtual reality (VR) systems, the interface and interaction design for immersive virtual environments have become a critical issue for VR application designers and developers. The previous design experience from conventional VR applications may not be effective anymore. This work investigated two types of menu interfaces (fixed menu and handheld menu) and three selection techniques, hand pointing with button press (Hand-BP), head pointing with button press (Head-BP), and head pointing with dwell (Head-DW), based on performance and subjective assessment. Results showed that the best performing selection technique for fixed menu was Hand-BP, while Head-BP was the most suitable and preferred selection technique for handheld menu. The limitations of different menu interfaces and selection techniques were discussed, and solutions were proposed to overcome the limitations that were found in the experiment. Based on the findings of this study, design guidelines were provided to help designers and developers choose the right menu interface and selection technique for different contexts of use and user groups.

Different Clinical Contexts of Use of Blood Neurofilament Light Chain Protein in the Spectrum of Neurodegenerative Diseases.

One of the most pressing challenges in the clinical research of neurodegenerative diseases (NDDs) is the validation and standardization of pathophysiological biomarkers for different contexts of use (CoUs), such as early detection, diagnosis, prognosis, and prediction of treatment response. Neurofilament light chain (NFL) concentration is a particularly promising candidate, an indicator of axonal degeneration, which can be analyzed in peripheral blood with advanced ultrasensitive methods. Serum/plasma NFL concentration is closely correlated with cerebrospinal fluid NFL and directly reflects neurodegeneration within the central nervous system. Here, we provide an update on the feasible CoU of blood NFL in NDDs and translate recent findings to potentially valuable clinical practice applications. As NFL is not a disease-specific biomarker, however, blood NFL is an easily accessible biomarker with promising different clinical applications for several NDDs: (1) early detection and diagnosis (i.e., amyotrophic lateral sclerosis, Creutzfeldt-Jakob disease, atypical parkinsonisms, sporadic late-onset ataxias), (2) prognosis (Huntington's disease and Parkinson's disease), and (3) prediction of time to symptom onset (presymptomatic mutation carriers in genetic Alzheimer's disease and spinocerebellar ataxia type 3).

A multifuncionalidade de aliás: valores semânticos em perspectiva funcional

Este artigo tem por objeto de estudo o elemento linguístico aliás, observado nos diferentes contextos de uso em que é recrutado. Segundo a Nomenclatura Gramatical Brasileira (NGB), aliás é classificado como palavra denotadora de retificação. Em gramáticas e dicionários de autores consagrados, esse item é classificado conforme a NGB e como advérbio. Durante a pesquisa, verificamos a flutuação categorial desse elemento, que também assume características de conjunção, conector reformulativo e operador argumentativo, além da mencionada classificação tradicional. Observamos sua frequência e usos, em textos de modalidade oral, do corpus Discurso & Gramática, sob a luz da Linguística Funcional Centrada no Uso. Os fatores analisados, calcados no aspecto semântico, são os seguintes: posições nos textos, frequência de uso, graus de escolaridade e gêneros textuais. A análise aponta que esse elemento, bastante utilizado no português do Brasil, serve às diversas funções discursivas, tais como: reformulação, retificação integral, retificação parcial, inclusão (de argumentos), dentre outras. Não obstante à classificação imposta pela NGB, os resultados apontam para uma versatilidade desse elemento linguístico, quando analisado nos contextos em que é instanciado.

Abstract A60: Evaluation of preanalytic variables in liquid biopsy tests for prostate cancer: Specimen acquisition and patient context factors that impact results

Abstract Cell-free DNA (cfDNA) and circulating tumor cell (CTC) enumeration and profiling serve as sources of tumor material to guide treatment decisions. Use of blood-based biomarker assays requires an understanding of factors outside the laboratory where the assay is performed that can influence the final reported result. The factors include preanalytical variables related to specimen acquisition, delivery and storage, and patient context variables. To address this question, our group activated an IRB-approved protocol to study the effect of variables associated with the factors mentioned above, including: (i) the order of blood being drawn in a single collection, (ii) collections done at different times of the day, (iii) collections repeated 1-14 days apart, (iv) patient fasting status, and (v) glucocorticoid use as an antiemetic. Our focus is on validated assays spanning different contexts of use in metastatic prostate cancer management, including: 1) a nuclear localized AR-V7 assay in circulating tumor cells (CTCs) as response indicator to androgen receptor (AR) signaling inhibitor vs. taxane based chemotherapy in the second line of therapy (Epic Sciences®, San Diego, CA); 2) a change in CTC number from any pretherapy value to zero post-therapy as a response indicator (CellSearch®, Menarini Silicon Biosystems); and 3) the detection of somatic mutations and copy number alterations in the AR pathway as resistance mechanism to abiraterone acetate in castration-resistant prostate cancer patients. Our pilot data currently include a cohort of 12 patients on which we aimed to study the effect of draw order on (i) the counts of CTC and ARV7 expression assessed by EpicScience® and (ii) the quality and quantity of cfDNA and mutation detected assessed by the analytically validated ThermFisher Oncomine® Pan-cancer cfDNA assay (Waltham, MA). Our initial analysis showed that the CTC and cfDNA results are mostly consistent across different draw orders, with slight variation at levels close to or below the limit of detection of the assay involved (such as 0.1% variant allele frequency of the ThermoFisher Oncomine® assay). We are expanding the sample size to further validate these results, perform additional statistical analysis, and include data from the Food and Drug Administration (FDA) cleared, CellSearch® CTC enumeration assay and MSK-ACCESS (Analysis of Circulating cfDNA to Examine Somatic Status), an ultrasensitive 129-gene cfDNA profiling assay that was developed internally at Memorial Sloan Kettering Cancer Center, recently approved by the New York State Department of Health, and launched in our Clinical Laboratory Improvement Amendment (CLIA)-certified molecular diagnostic laboratory. The results of this study will provide evidence to inform the design of preanalytical sample collection and inform how to use these tests in clinical practice. Citation Format: Dana Tsui, Ethan S. Barnett, Kelli Bramlet, Joseph Schonhoft, Ruben Rizzi, Howard I. Scher. Evaluation of preanalytic variables in liquid biopsy tests for prostate cancer: Specimen acquisition and patient context factors that impact results [abstract]. In: Proceedings of the AACR Special Conference on Advances in Liquid Biopsies; Jan 13-16, 2020; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(11_Suppl):Abstract nr A60.

La escritura medieval de la Corona de Aragón (1137-1474)

Ce travail présente, de manière schématique, l'évolution des formes adoptées par l'écriture dans la Couronne d'Aragon de 1137 à 1474. La période chronologique analysée comprend les variantes exactes de la gothique et de l'humanistique. Ce n'est pas seulement l'aspect extérieur et la chronologie de chacune qui y sont décrits, on a prétendu, aussi, y reconstruire les différents contextes en usage de l'écriture et les caractéristiques exactes qu'elle a adopté en tenant compte de la diversité de sa fonction. Etant donné que le terrain le plus étudié est la Chancellerie royale, sa documentation agit en tant que fil conducteur du travail. Cela n'empêche pas que l’on démontre, à travers des textes, d'autres matériaux (épigraphiques, phylactères, de livres, etc.) qui permettront de reconstituer l'histoire complète de l'écriture médiévale employée dans les différents milieux.

A desambiguação lexical durante a compreensão leitora em inglês como língua estrangeira

O objetivo deste estudo é analisar a desambiguação lexical durante a compreensão leitora em inglês como língua estrangeira. Sabe-se que, para desambiguar uma palavra, o leitor normalmente recorre ao contexto; assim, a pesquisa está fundamentada teoricamente em questões que dizem respeito à definição de contexto, e abarca uma teoria lexical denominada Hipótese da Qualidade Lexical (HQL) que explica como as características das palavras (aspectos fonológicos e semânticos, por exemplo), são parte fundamental da compreensão leitora. Este trabalho faz parte de um projeto maior, ainda em andamento, que aqui, traz um estudo de caso que analisa a ambiguidade das palavras record e track em diferentes contextos de uso. Os resultados preliminares mostram que as características das palavras, bem como os diferentes tipos de contexto não estão desvinculados do fenômeno da desambiguação, mas o leitor nem sempre tem a ciência de que precisa desambiguar, ainda que compreenda o que leu.

Realizaciones temporales de la construcción fraseológica [Ssing PREP Ssing

El objetivo de este trabajo es realizar una descripción tanto formal como semánticopragmática de las realizaciones de valor temporal de la construcción binomial [Ssing PREP Ssing], de uso habitual en español. Para ello se lleva a cabo un análisis detallado, basado en datos de corpus, que incluye la justificación de su carácter fraseológico a través de los rasgos de frecuencia y de fijación, así como la explicación de los significados detectados en distintos contextos de uso y de las diferencias fundamentales entre las preposiciones empleadas y los sustantivos temporales que cubren el slot. En el análisis se presta especial atención a los datos de coocurrencia léxica.

Context and technology use: Opportunities and challenges of the situated perspective in technology acceptance research

AbstractThe purpose of this paper is to explore the implications of the situative perspective in understanding technology acceptance. Briefly, this is the position that holds technology acceptance is influenced by the context of use, which determines the situations and activities in which the technology is employed. Specifically, we review the literature studying the relationship between political engagement and social media use. We examine the link between individuals' political beliefs and political engagement on their acceptance and use of social media extending the core factors of the technology acceptance model. Using a sample drawn from a pre‐university college physics program, we test a structural path model, using WarpPLS, and reproduce the oft‐reported link between social media use and political engagement and showing that social media use for political engagement influences individuals' perceptions of social media technology. These results are interpreted with respect to the situative perspective, specifically, we employ the ecological psychology notion of affordances to understand how social media technology is disrupting traditional political discourse and creating new forum for public discourse and political engagement. Our study demonstrates the value of considering the social dimension in understanding individuals' technology acceptance decisions and behaviors. Understanding the social dimension pf technology acceptance is necessary for modeling user technology acceptance and key to successful implementation initiatives and life cycle management of educational technologies. Practitioner NotesWhat is already known about this topic Using social media varies by individual characteristics and by instrumental use, creating different contexts of use, such as online political engagement. What this paper adds Using social media for political engagement influences perceptions of usefulness and ease of use. A fuller account of technology acceptance must include social and affective determinants in addition to cognitive factors. Implications for practice and/or policy Understanding technology acceptance as a social process requires an account of the purposes and functions of technology within spheres of activity. Thus, understanding the social dimension of technology acceptance appears key area of research for educational technologists working on implementation and life‐cycle management of educational technologies.

SEXUAL DIMORPHISM IN PLASMA BETA-SECRETASE 1 CONCENTRATIONS IN COGNITIVELY NORMAL INDIVIDUALS AT RISK FOR AD: CROSS-SECTIONAL AND LONGITUDINAL STUDIES

The development of effective disease-modifying treatments for early Alzheimer's disease (AD) and targeting β-site amyloid precursor protein cleaving enzyme 1 (BACE1)-targeted requires biomarker-drug co-development strategies, including the validation and qualification of accessible and non-invasive biological markers for different contexts of use. Cross-sectional and longitudinal studies demonstrated that plasma and cerebrospinal fluid (CSF) concentrations of BACE1 closely correlate with each other. We conducted both cross-sectional and longitudinal explorative studies in a cohort of individuals with subjective memory complaint (SMC), a condition at risk for AD, to investigate whether key biological factors such as sex, APOE ε4allele, and age affect plasma BACE1 concentrations. SMC individuals were recruited from the “INveStIGation of AlzHeimer's PredicTors in Subjective Memory Complainers” (INSIGHT-preAD) study, a university-based cohort which is part of the Alzheimer Precision Medicine Initiative (APMI) and its Cohort Program (APMI-CP). In the cross-sectional analysis, we found that baseline plasma BACE1 concentrations were highly significantly increased in females compared to males (p<0.001). Women showed a highly significantly increased plasma BACE1 concentrations compared to men, at all the three investigated time intervals (p<0.001). No difference regarding the longitudinal trajectories of plasma BACE1 concentrations was found between women and men. There was no significant effect of age and APOE ε4carrier status neither on overall BACE1 concentrations nor on BACE1 concentrations evolution. There was a highly significant decrease in plasma BACE1 concentrations in the whole sample of SMC individuals over time (p<0.001). We did not find any significant impact of two-way interactions between age and sex, age and APOE ε4 allele, sex and APOE ε4 allele on BACE1 plasma concentrations either at baseline or longitudinally. Thus, we demonstrate that the impact of a sexual-dimorphism on plasma BACE1 concentrations is irrespective of age and time. Evidence of the potential impact of a sexual dimorphism on the concentration and activity of BACE1 may be a relevant missing design component contributing to the failure of negative clinical BACE1 inhibitor therapy trial outcomes. Our results indicate that the impact of a sexual dimorphism on plasma BACE1 should be considered in further biomarker validation and qualification studies and in clinical BACE1 trials.

The shifting perception of Japanese BELF users towards English: a case study

AbstractThis paper examines attitudes of Japanese business people towards English by interviewing Japanese construction company employees working on international projects in Asian countries, where English is used as a lingua franca (ELF). The engineers took part in an intensive English course provided by their company before being transferred to overseas offices. Conducting individual/focus-group interviews multiple times during and after the English course, the study sheds light on the participants’ ambivalent and shifting perception of the language, which has both communicative and identifying function in different contexts of use. While these BELF (English as a business lingua franca) users were more content-focused and critical about a teacher’s form-focused approach during the intensive English language training, they are likely to identify more with native-speakers’ English rather than with their own English communication in BELF environments. The paper discusses that there are two reasons for their adherence to “standard” English, referring to the impact of “standard” English ideology (Cogo 2015, 2016b; Seidlhofer 2011, 2018) and social power (French and Raven 1959) that their interlocutors possess. First, the participants are constrained by their past learning experience as EFL (English as a foreign language) learners (Iino and Murata 2016) with little exposure to varieties of English other than the Inner Circle English models (Kachru 1992). Second, they believe in the advantage of using “correct” or “proper” English in producing a good image of their company or themselves. More specifically, while the participants regard English predominantly as a tool to fulfil their communicative goals when working with interlocutors who have relatively less power (e.g. subordinates, subcontractors), they feel that they need to speak “proper” English when communicating with people with more power and authority (e.g. superiors, clients), because they believe it is more relevant and accepted by the wider public. In other words, the result shows how the “standard” English ideology is deep-seated in the workplace communication discourse.

РОЗВИТОК ІНШОМОВНОЇ КОМУНІКАТИВНОЇ КОМПЕТЕНЦІЇ МАЙБУТНІХ ВЧИТЕЛІВ ІНОЗЕМНОЇ МОВИ ЗА ДОПОМОГОЮ МЕТОДУ ІНТЕЛЕКТ-КАРТ

The article deals with the issues of applying mind maps to develop foreign language communicative competence in training future foreign language teachers. According to the Common European Framework of Reference for Languages, Communicative Competence is divided into: Linguistic Competence: it refers to the ability of producing utterances in an efficient way in all its grammatical levels. It includes such competences as: lexical, grammatical, semantic, phonologic and orthographic competence. Sociolinguistic Competence: it is the ability of understanding and producing different utterances in different contexts of use where different factors play an important role, such as the relationship between participants, their situation, etc. Aspects to take into account here are social relationships markers, politeness norms, popular wisdom expressions, register differences, dialect and accent differences, etc. Pragmatic Competence: It makes reference to the ability of acting efficiently in a language taking into account grammatical forms and meaning to complete a text in different communicative events.One of the effective methods for the development of foreign language communicative competence is Mind Mapping. The Mind Mapping process involves a unique combination of imagery, colour and visual-spatial arrangement which is proven to significantly improve recall when compared to conventional methods of note-taking and learning by rote. The mind map format is becoming an alternative to the traditional way of making notes, storing large quantities of educational information by a student for further use. Mind maps are graphically expressed processes of multidimensional thinking; they show the hierarchical interrelation of ideas. They’re great for team use, as well as for all types of speech activity.Application of mind maps is fully efficient for the development of foreign language communicative competence in training future foreign language teachers.

Assessing Computational Model Credibility Using a Risk-Based Framework: Application to Hemolysis in Centrifugal Blood Pumps.

Medical device manufacturers using computational modeling to support their device designs have traditionally been guided by internally developed modeling best practices. A lack of consensus on the evidentiary bar for model validation has hindered broader acceptance, particularly in regulatory areas. This has motivated the US Food and Drug Administration and the American Society of Mechanical Engineers (ASME), in partnership with medical device companies and software providers, to develop a structured approach for establishing the credibility of computational models for a specific use. Charged with this mission, the ASME V&V 40 Subcommittee on Verification and Validation (V&V) in Computational Modeling of Medical Devices developed a risk-informed credibility assessment framework; the main tenet of the framework is that the credibility requirements of a computational model should be commensurate with the risk associated with model use. This article provides an overview of the ASME V&V 40 standard and an example of the framework applied to a generic centrifugal blood pump, emphasizing how experimental evidence from in vitro testing can support computational modeling for device evaluation. Two different contexts of use for the same model are presented, which illustrate how model risk impacts the requirements on the V&V activities and outcomes.