Use Of Definitions Research Articles

New Framework for Computing a General Local Self-Diffusion Coefficient Using Statistical Mechanics.

Widely applicable, modified Green-Kubo expressions for the local diffusion coefficient (Dl) are obtained using linear response theory. In contrast to past definitions in use, these expressions are statistical mechanical results. Molecular simulations of systems with anisotropic diffusion and an inhomogeneous density profile confirm the validity of the results. Diffusion coefficients determined from different expressions in terms of currents and velocity correlations agree in the limit of large systems. Furthermore, they apply to arbitrarily small local regions, making them readily applicable to nanoscale and inhomogeneous systems where knowledge of Dl is important.

Taxonomies of technological knowledge in higher education: A mapping of students’ perceptions

This paper presents the findings from a qualitative study exploring students’ perceptions of what constitutes technological knowledge. Technological knowledge dimensions from previous literature do not seem to be student-led, but rather suggested by the authors. It is therefore important to incorporate student views in order to create a more evidence-based taxonomy. Previous taxonomies of technological knowledge are also heavily linked to engineering-related disciplines, however definitions for use across the field of education and learning technologies would be helpful. In this study, a sample of student volunteers were interviewed about their understanding of technology enhanced learning and technological knowledge. The students were from a range of disciplines, not just engineering and science, so that technology knowledge for the general student population would be represented. An inductive thematic analysis was then carried out on the interview transcripts. Three knowledge types were derived from the thematic analysis: practical knowledge; structural knowledge; and computer science knowledge. These three empirically-derived technological dimensions were then mapped onto existing taxonomical structures from the literature. Finally, this paper discusses the implications of the student-generated dimensions for educators. Implications for practice or policy: Educators may need to consider how student-generated types of technological knowledge map onto existing technological knowledge structures and Bloom’s taxonomy. Educators can use the types of technology knowledge to target their teaching to their learners’ required knowledge level.

Predictors of E-cigarette and Cigarette Use Trajectory Classes from Early Adolescence to Emerging Adulthood Across Four Years (2013-2017) of the PATH Study.

This study examines predictors of trajectories of cigarette and e-cigarette use among a cohort of US adolescents transitioning into young adulthood. Comparing trajectories of each tobacco product is important to determine if different intervention targets are needed to prevent progression to daily use. Latent trajectory class analyses identified cigarette and e-cigarette use (never, ever excluding past 12-month, past 12-month (excluding past 30-day (P30D)), P30D 1-5 days, P30D 6+ days) trajectory classes, separately, among US youth (12-17; N = 10,086) using the first 4 waves (2013-2017) of data from the nationally representative PATH Study. Weighted descriptive analyses described the class characteristics. Weighted multinomial logistic regression analyses examined demographic, psychosocial, and behavioral predictors of class membership. Younger adolescents 12-15 years had lower tobacco use compared to 16-17 year olds and less stable classes. In the 16-17 year group, there were five unique trajectories of cigarette smoking, including a Persistent High Frequency class. Four e-cigarette use trajectories were identified; but not a persistent use class. Shared predictors of class membership for cigarettes and e-cigarettes included mental health problems, other tobacco use, marijuana use, and poorer academic achievement. Male sex and household tobacco use were unique e-cigarette trajectory class predictors. There was no evidence that initiation with e-cigarettes as the first product tried was associated with cigarette progression (nor cigarettes as first product and e-cigarette progression). Interventions should focus on well-established risk factors such as mental health and other substance use to prevent progression of use for both tobacco products. Using nationally representative data and definitions of use that take into account frequency and recency of use, longitudinal 4-year trajectories of e-cigarette and cigarette use among US adolescents transitioning into young adulthood were identified. Results among 16-17-year olds revealed a class of persistent high frequency cigarette smoking that was not identified for e-cigarette use. Cigarette use progression was not associated with e-cigarettes as the first product tried. Risk factors for progression of use of both products included mental health and other substance use, which are important prevention targets for both tobacco products.

UK PERSPECTIVE ON DEVELOPING REGULATIONS FOR AUTONOMOUS SHIPS

The scope of this paper is the development of regulation for remotely operated and autonomous ships. From a UK perspective, it discusses an enquiry into the United Nations Conventions for the Law of the Sea and the impact of autonomy. It explores the outcome of the International Maritime Organisation’s Regulatory Scoping Exercises on Maritime Autonomous Surface Ships and the next steps. The paper shares the regulatory developments at the different UK domestic legislative levels. The Future of Transport consultation is discussed, which includes potential new definitions for use in primary legislation. The Workboat Code is being updated to include emerging technologies, the paper touches on the methodology used to support the inclusion of remotely operated unmanned vessels as a new Annex. Finally, the current approach for managing the certification of remote operated and autonomous ships is discussed.

Creating ontological definitions for use in science

Ontologies aim to represent the world in terms of uniquely defined classes and their properties which are expressed as relationships with other classes. They are becoming widely used in science to improve clarity, searching, inference and the ability to link data from different sources. Ontological definitions are descriptions that represent the essential properties of classes of entities (which include objects, object attributes and processes) that distinguish them from other classes. Classes have unique IRIs (Internationalised Resource Identifiers) that can be used for searching; they also have labels which are words of phrases that people can use to identify the class in passages of text or tables. This article provides a brief guide to help with writing good ontological definitions. The standard format of such a definition of a class, A, is: ‘a B that C’ or its semantic equivalent, where A is the class being defined, B is a parent class and C describes a set of properties of A that distinguish it from other members of B.

The Use of Myth in Literature

This study is entitled "The Use of Myth in Literature". It is an attempt to demonstrate the way myth is used in literary texts. The primary objective of the study is to present the types and mechanisms of myth usage in literature. Thus, the current study is concerned with how myth is reflected in literary works. The study is divided into two sections. The focus of the first section is on the term, concept and definition of Use, following this, mechanisms of Use are highlighted. The second section deals with the motives of Use and its types. Finally, the main conclusions and references of the study are presented.

DOP35 Increasing incidence of pouchitis among patients undergoing ileal pouch-anal anastomosis between 1996 and 2018: A population-based Danish cohort study

Abstract Background Current knowledge regarding the epidemiology of pouchitis is based on highly selected, mostly single-center, patient cohorts. Our objective was to prospectively determine the population-based incidence of pouchitis in patients with ulcerative colitis (UC) in the first 2 years after ileal pouch-anal anastomosis (IPAA) and analyze time trends of the incidence of pouchitis. Methods We used national registries to establish a population-based cohort of all Danish patients undergoing proctocolectomy with IPAA UC between 1996 and 2018. The primary outcome was the development of pouchitis within the first 2 years after IPAA, evaluated by time period of IPAA. The period of IPAA was categorized as follows: 1996–2000 (pre-biologic-1), 2001–2005 (pre-biologic-2), 2006–2010 (early-anti-TNF), 2011–2014 (expanding anti-TNF), 2015–2018 (current biologic). Pouchitis was defined using a previously developed case-finding definition for use in administrative claims data. Kaplan Meier and Cox Proportional Hazard modeling were utilized in the evaluation of time to development of pouchitis. Results We identified 1,664 patients that underwent an IPAA for UC. The cumulative incidence of pouchitis in the 2 years after IPAA increased throughout the study period, from 40% in 1996–2000, (95% CI:35%-46%) to 55% in 2015–2018, (95% CI:48%-63%, Table 1). Patients undergoing surgery between 2015–2018 also demonstrated an increased risk of pouchitis compared to the earliest study period (1996–2000) after adjusting for sex, age, and socioeconomic status (Hazard Ratio [HR] 1.57, 95% CI:1.20–2.05, Table 2, Figure 1). In a separate model adjusting for the same clinical and demographic factors, there was no significant relationship between the preoperative use of anti-tumor necrosis factor alpha therapy use and the risk of pouchitis when evaluated in the entire population (HR 1.14, 95% CI:0.93–1.40) and when evaluated by time period of surgery. Conclusion This first population-based study demonstrated a 15% absolute and 38% relative increase in the incidence of pouchitis among patients undergoing surgery between 1996 and 2018, with the greatest cumulative incidence of pouchitis demonstrated in the most recent era (2015–2018). The striking increase in the incidence of pouchitis highlights the need for further research into causes and prevention of pouchitis.

Quantitative assessment of information quality in textual sources for landslide inventories

Landslide research chiefly relies on digital inventories for a multitude of spatial, temporal, and/or process analyses. In respect thereof, many landslide inventories are populated with information from textual documents (e.g., news articles, technical reports) due to effectiveness. However, information detail can vary greatly in these documents and the question arises whether such textual information is suitable for landslide inventories. The present work proposes to define the usefulness of textual source types as a probability to find landslide information, weighted with adaptable parameter requirements. To illustrate the method with practical results, a German landslide dataset has been examined. It was found that three combined source types (administrative documents, expert opinions, and news articles) give an 89 % chance to detect useful information on three defined parameters (location, date, and process type). In conclusion, the definition of usefulness as a probability makes it an intuitive, quantitative measure that is suitable for a wide range of applicants. Furthermore, a priori knowledge of usefulness allows for focusing on a few source types with the most promising outcome and thus increases the effectiveness of textual data acquisition and digitalisation for landslide inventories.

The effect of the context in clarifying the summaries, weighing the possibilities, and deciding the obvious (Sultan Alolama' as a Model) An Empirical Study

The idea of the research at first was to determine the importance of the context as it is an asset considered by scholars and fundamentalists in particular، as it has a great impact on the interpretation of fundamentalist texts، and its impact appears in the investigations of words from the uttered and understood، the overall and the interpreted، the command، the prohibition، the general and specific، the absolute and the restricted، and this The fundamentalist effect has its impact on the branches، through jurisprudence issues، and it is decided by scholars that contextual evidence is verbal and maqam، and this has no effect in determining the meaning intended from the context of speech. And I saw a clear interest in the context of Imam Al-Aziz through his statements، as he said: “The context is a guide to clarifying the generalities، weighing the probabilities، and deciding the obvious، and all of that is by definition of use.” These three have been addressed in addition to the impact of context on deletion and the impact of context specification، I concluded with a number of results، including that Imam Al-Ezz was an encyclopedist، and he used context in his books as it is one of the fundamentals investigations، and it is often used in the indefinite in the context of the conditional، and that the context for the fundamentalists has multiple names such as (speech context، system context، clear pronunciation، marketed for speech The word market) which is understood from the discourse by means of presumptions، and it helps to explain the outline، clarify what is meant by it and understand it correctly، clarifies what has been formed from the words، establishes the clear from the text and the apparent، guards the meaning and guides on what is omitted from speech if there is evidence for it and is dedicated to some of its requirements.

Defining Collaboration Through the Lens of a Delphi Study: Student Affairs and Academic Affairs Partnerships in Residential Learning Communities

Evidence suggests that collaborations between academic affairs and student affairs can foster student success both inside and outside of the classroom. Residential learning communities (RLCs) are a popular avenue by which these two divisions can find collaborative opportunities to integrate students’ curricular and cocurricular experiences. Although this strategy can be rich in student success rewards, academic affairs, and student affairs face challenges as they work to overcome cultural and structural differences. One of these challenges may simply be the lack of a shared interpretation of collaboration. The purpose of this study is to arrive at a consensus definition of collaboration within the context of RLCs. We engaged RLC scholars and practitioners in a Delphi study to create a comprehensive definition for use in RLC program assessment and development resulting in the following definition: Collaboration between academic and student affairs is the continuous process of cultivating an interdependent relationship where each stakeholder is mutually committed to working toward the shared purpose of holistic student learning. This definition serves as a springboard for academic affairs and student affairs RLC collaborators to strive for continuous processes, interdependent relationships, and commitment to a shared purpose.

Pregestational Diabetes Exposure In Utero: Validation of a Definition for Use in Administrative Data

ObjectiveOur aim in this study was to determine the best administrative data case definition for pregestational diabetes exposure. MethodsWe compared the performance of case definitions for pregestational diabetes exposure within the administrative health data housed in the Manitoba Population Health Research Repository at the Manitoba Centre for Health Policy with an identified population of women in whom the diagnosis of pregestational diabetes was known from the clinical database of the Manitoba Diabetes Education Resource for Children and Adolescents (DER-CA) (August 12, 1989 through January 28, 2015). The DER-CA database contains maternal diabetes status during pregnancy and also includes women diagnosed with type 2 diabetes in childhood whose pregnancies were thus all complicated by pregestational diabetes exposure. Linkage of mother–child dyads is possible within the Repository. Diagnosis codes from the International Classification of Diseases---ninth or tenth revision and physician tariff codes were used to identify diabetes in the biologic mothers of children with type 2 diabetes identified from the DER-CA database. The timing of the diagnosis of diabetes in the mother with respect to the gestational age of the pregnancy was determined. ResultsThe best administrative definition of pregestational diabetes exposure was any incident code for diabetes in the mother before the pregnancy of the index child or within the first 25 weeks of pregnancy (sensitivity: 84.77%; positive predictive value: 92%). ConclusionThe definition cited can be used to define pregestational diabetes exposure in studies utilizing administrative data.

Methodology for composite materials shrinkage definition for use in shipbuilding and marine technology

Deformations of steel material in shipbuilding and marine technology applications as a result of mechanical or temperature influences are a well-known problem. However, in the modern shipbuilding industry, the application of alternative materials, especially composite materials, in the structure and for the equipment of the ship is increasingly represented. Consequently, there is a need to determine the deformation and change of characteristics of such composite materials as a result of various mechanical, and especially temperature influences that cause the so-called shrinkage. The basic composite production process involves connecting the matrix with a catalyst and accelerators that create temperature, then the material shrinks by cooling when it can change its dimensions and characteristics. Also, in order to achieve the best possible mechanical properties, composite materials are specially heated and then cooled according to strictly defined processes and curves. The ability to predict the characteristics and parameters of such deformations is important in the context of the application of composite materials. To define such deformations, different methods are used within individual numerical solvers, whose results can differ significantly from each other. Therefore, the authors in this paper present an established methodology for predicting mechanical and temperature deformations, and modelling of composite materials, based on the analysis of analytical methods and numerical solvers with the aim of defining the most accurate numerical solver. By applying the presented methodology, it is expected to raise the level of accuracy and quality of composite materials production as well as to raise the quality of design solutions and efficiency of production procedures during shipbuilding in particular, but also within different marine technology applications and during the product’s life cycle.

Refractory Orofacial Pain: Is It the Patient or the Pain?

To highlight and discuss the term "refractory" when used to describe pain conditions and its application to orofacial pain, as well as to highlight the factors that must be considered in a refractory patient. A scoping review of recent publications (2010 to 2021) applying the term "refractory" to orofacial pain was conducted, and this paper presents their limitations and definitions. The term "refractory" is often used to describe pain instead of "persistent" or "nonresponsive." There are clear definitions in the use of refractory for migraine, cluster headaches, and other nonheadache disorders. Currently, the term is applied to pain conditions in order to alter the patient pathway of treatment, sometimes to escalate a patient from one care sector to another and sometimes to escalate treatment to more costly surgical interventional techniques. There is a need for a clear definition for use of the term "refractory" in orofacial pain conditions, excluding migraine and cluster headaches. In addition, there is a requirement for a consensus on the implications of the use of refractory when assessing and managing patients.

Classifying Oligometastatic Non-Small Cell Lung Cancer.

Simple SummaryAround half of patients with non-small cell lung cancer (NSCLC) have metastatic disease at the time of diagnosis. Some patients will have a limited number of metastatic sites, termed oligometastasis, rather than widespread disease. Aggressive treatment of oligometastasis has been supported by improved survival rates in retrospective studies, meta-analyses, and randomized phase II trials. Patient selection for aggressive local treatment of oligometastatic NSCLC would be facilitated by a common definition of what constitutes oligometastasis. We review the definitions of oligometastatic NSCLC proposed by consensus statements and those used in current treatment guidelines and previous trials of local consolidative therapy.An oligometastatic cancer state was first postulated in the 1990s by Hellman and Weichselbaum and described limited metastatic spread to a single or few sites of disease. It was hypothesized that this metastatic entity falls along a continuum of the natural history of cancer progression from a localized primary tumor to widespread metastases. Support for oligometastatic non-small cell lung cancer (NSCLC) has since been provided by multiple retrospective studies and then prospective randomized trials demonstrating better survival in this patient population after aggressive consolidative treatment. However, the lack of a universal definition of oligometastatic NSCLC has hindered a comparison between different studies and prevented well-defined recommendations for local consolidative treatment in this patient population. Attempts have been made to establish a common definition for use in clinical management and for the identification of inclusion criteria for future trials. In this review, we seek to summarize the current definitions of oligometastatic NSCLC based on recent expert consensus statements, previous randomized trials, and current treatment guidelines and to highlight the continued variability in current practice.

Is It Really Home-Based? A Commentary on the Necessity for Accurate Definitions across Exercise and Physical Activity Programmes.

Background: There is wide discrepancy in how published research defines and reports home-based exercise programmes. Studies consisting of fundamentally different designs have been labelled as home-based, making searching for relevant literature challenging and time consuming. This issue has been further highlighted by an increased demand for these programmes following the COVID-19 pandemic and associated government-imposed lockdowns. Purpose: To examine what specifically constitutes home-based exercise by: (1) developing definitions for a range of terms used when reporting exercise and physical activity programmes and (2) providing examples to contextualise these definitions for use when reporting exercise and physical activity programmes. Methods: A literature search was undertaken to identify previous attempts to define home-based exercise programmes. A working document, including initial definitions and examples were developed, which were then discussed between six experts for further refinement. Results: We generated definitions for universal key terms within three domains (and subdomains) of programme design: location (home-based, community/centre-based, or clinical setting), prescription (structured or unstructured) and delivery (supervised, facilitated, or unsupervised). Examples for possible combinations of design terms were produced. Conclusions: Definitions will provide consistency when using reporting tools and the intention is to discuss the issues presented as part of a Delphi study. This is of paramount importance due to the predicted increase in emerging research regarding home-based exercise.

Vitamin C in the Prevention of Contrast-induced Nephropathy among High-risk Patients Undergoing Coronary Angiogram: A Meta-analysis

Background: Contrast-Induced nephropathy (CIN) is one of the leading causes of acute kidney injury. The most common procedures associated with CIN are coronary angiography and contrast enhanced computed tomography (CT) [1]. The most common definition in use is an increase in serum creatinine (SCr) of >25% of the baseline values occurring following the intravascular administration of contrast media without an alternative explanation [2]. Generation of reactive oxygen species is thought to play a role in the pathogenesis of CIN, hence researches have been conducted into the potential role of antioxidants in the prevention of contrast-induced nephropathy [3]. Vitamin C, a potent antioxidant in humans has the ability to oxidize free radicals, and has been studied in different trials to measure its ability to prevent CIN among patients undergoing coronary angiogram.
 Objective: To determine if vitamin C prevents CIN among High-risk patients (Creatinine Clearance <60 ml/min/m2, Diabetics, and on administration of high-volume contrast media).
 Methodology: All studies, limited to randomized clinical trials were sought for this analysis through PubMed, the Cochrane Library, ClinicalTrials.gov. Database was searched using the terms “vitamin C”, “Prevention”, “acute kidney injury” and “contrast-induced nephropathy”. Adult patients (40-90 years old) with Creatinine Clearance of <60 ml/min/m2 or baseline creatinine >1.2 mg/dl, Diabetes Mellitus Type II, and were administered with high-volume contrast media (>100ml) undergoing coronary angiogram were included in the study. Exclusion Criteria were patients with normal baseline renal function, without risk factors for CIN, with EGFR < 30 ml/min/m2, with regular intake of Vitamin C and were on dialysis. Statistical data were obtained using Review Manager (RevMan) Version 5.3 freeware program. P Value was obtained using the Cochran–Mantel–Haenszel test (CMH). Included patients were given Vitamin C at doses of 1 gram to 3 grams, taken orally or administered intravenously pre-and post coronary angiogram.
 Results: Seven hundred and one (N=701) patients were included in this meta-analysis. CIN occurred in 3.5% of patients (N=25) in the ascorbic acid group and in 6% of patients (N= 42) in the placebo group (p value of 0.03).
 Conclusion: Vitamin C given at doses 1 gram to 3 grams in combination with hydration prior to coronary angiogram may have a significant effect in the prevention of CIN in high-risk patients.

Urinary Cotinine and Cotinine + Trans-3'-Hydroxycotinine (TNE-2) Cut-points for Distinguishing Tobacco Use from Nonuse in the United States: PATH Study (2013-2014).

Determine the overall, sex-, and racially/ethnically-appropriate population-level cotinine and total nicotine equivalents (TNE-2, the molar sum of the two major nicotine metabolites) cut-points to distinguish tobacco users from nonusers across multiple definitions of use (e.g., exclusive vs. polytobacco, and daily vs. non-daily). Using Wave 1 (2013-2014) of the U.S. Population Assessment of Tobacco and Health (PATH) Study, we conducted weighted Receiver Operating Characteristic (ROC) analysis to determine the optimal urinary cotinine and TNE-2 cut-points, stratified by sex and race/ethnicity. For past 30-day exclusive cigarette users, the cotinine cut-point that distinguished them from nonusers was 40.5 ng/mL, with considerable variation by sex (male: 22.2 ng/mL; female: 43.1 ng/mL) and between racial/ethnic groups (non-Hispanic other: 5.2 ng/mL; non-Hispanic black: 297.0 ng/mL). A similar, but attenuated, pattern emerged when assessing polytobacco cigarette users (overall cut-point = 39.1 ng/mL, range = 5.5 ng/mL-80.4 ng/mL) and any tobacco users (overall cut-point = 39.1 ng/mL, range = 4.8 ng/mL-40.0 ng/mL). Using TNE-2, which is less impacted by racial differences in nicotine metabolism, produced a comparable pattern of results although reduced the range magnitude. Because of similar frequency of cigarette use among polytobacco users, overall cut-points for exclusive cigarette use were not substantially different from cut-points that included polytobacco cigarette use or any tobacco use. Results revealed important differences in sex and race/ethnicity appropriate cut-points when evaluating tobacco use status and established novel urinary TNE-2 cut-points. These cut-points may be used for biochemical verification of self-reported tobacco use in epidemiologic studies and clinical trials.

Defining Strategic Communication : An Almost Impossible Challenge, But Perhaps There Is Still A Solution

After the 9/11 terrorist attacks the term „strategic communication” became widely used by political and military leaders as well. Shortly, it became a kind of a ‘buzzword’. As a result, today there are many definitions in use to describe it. However, we are still facing lots of challenges if we wish to grasp the real meaning of this term. For a better understanding, and built on the research done so far, the author presents a possible interpretationof strategic communication based on some new methodologies and suggests a new approach and definition and, by his opinion, the main actors are the states and the armed forces.

Development and Validation of a Syndrome Definition to Identify Suspected Nonfatal Heroin-Involved Overdoses Treated in Emergency Departments.

The Centers for Disease Control and Prevention (CDC) works closely with states and local jurisdictions that are leveraging data from syndromic surveillance systems to identify meaningful changes in overdose trends. CDC developed a suspected nonfatal heroin overdose syndrome definition for use with emergency department (ED) data to help monitor trends at the national, state, and local levels. This study assesses the percentage of true-positive unintentional and undetermined intent heroin-involved overdose (UUHOD) captured by this definition. CDC applied the UUHOD definition to ED data available in CDC's National Syndromic Surveillance Program (NSSP). Data were analyzed from 18 states that shared access to their syndromic data in NSSP with the CDC overdose morbidity team. Data were analyzed using queries and manual reviews to identify heroin overdose diagnosis codes and text describing chief complaint reasons for ED visits. The percentage of true-positive UUHOD was calculated as the number of true-positives divided by the number of total visits captured by the syndrome definition. In total, 99 617 heroin overdose visits were identified by the syndrome definition. Among 95 323 visits identified as acute heroin-involved overdoses, based on reviews of chief complaint text and diagnosis codes, 967 (1.0%) were classified as possible intentional drug overdoses. Among all 99 617 visits, 94 356 (94.7%) were classified as true-positive UUHOD; 2226 (2.2%) and 3035 (3.0%) were classified as "no" and "maybe" UUHOD, respectively. Analysis of the CDC heroin overdose syndrome definition determined that nearly all visits were captured accurately for patients presenting to the ED for a suspected acute UUHOD. This definition will continue to be valuable for ongoing heroin overdose surveillance and epidemiologic analysis of heroin overdose patterns. CDC will evaluate possible definition refinements as new products and terms for heroin overdose emerge.

Substitution and complementarity in the use of health information exchange and electronic medical records

ABSTRACT While considerable literature has addressed the separate use of health information systems, limited research has examined how the use of one system changes following the implementation of another. We address this gap in the literature by developing and testing hypotheses about substitution and complementarity in physicians’ use of health information exchange (HIE), which merges patient data from multiple sources, following the implementation of a local electronic medical record (EMR) system. The hypotheses are anchored in theories foundational to understanding the motivation for information seeking behaviour. The hypotheses are tested with unique data, recorded in system log files, that describe HIE use by physicians in an emergency department before and after EMR implementation. The findings confirm that system use is characterised by substitution when it is defined dichotomously as whether the system is accessed or not (lower HIE access rates after EMR implementation) and by complementarity when it is defined as the extent of system use (higher volume and duration of HIE use after EMR implementation). Our findings suggest that the information seeking literature has underestimated the explanatory value of the cost-benefit approach and the occurrence of complementarity in system use because of its overreliance on a narrow definition of use.