Machine learning approaches to identifying social determinants of health in electronic health record clinical notes

Social determinants of health (SDH) represent the complex set of circumstances in which individuals are born, or with which they live, that impact health. Relatively little attention has been given to processes needed to extract SDH data from electronic health records. Despite their importance, SDH data in the EHR remains sparse, typically collected only in clinical notes and thus largely unavailable for clinical decision making. I focus on developing and validating more efficient information extraction approaches to identifying and classifying SDH in clinical notes. In this dissertation, I have three goals: First, I develop a word embedding model to expand SDH terminology in the context of identifying SDH clinical text. Second, I examine the effectiveness of different machine learning algorithms and a neural network model to classify the SDH characteristics financial resource strain and poor social support. Third, I compare the highest performing approaches to simpler text mining techniques and evaluate the models based on performance, cost, and generalizability in the task of classifying SDH in two distinct data sources.Doctor of Philosoph

COMBINING HUMAN FACTORS AND DATA SCIENCE METHODS TO EVALUATE THE USE OF FREE TEXT COMMUNICATION ORDERS IN ELECTRONIC HEALTH RECORDS

Medication errors are a leading cause of death in the United States. Electronic Health Records (EHR) along with Computerized Provider Order Entry (CPOE) are considered promising ways to reduce these errors. However, EHR systems have not eliminated medication errors. Moreover, in some cases they have facilitated errors due to issues such as poor usability and negative effects on clinical workflows. The use of unexpected free text within a CPOE system can serve as a marker that the system does not adequately support clinical workflow. Prior studies have looked at the use of free text within medication orders, but the inclusion of medication related information in communication for non-medication orders (CNMOs), a type of free text order, has not been adequately studied. This mixed-methods study identified the prevalence, nature and reasons for the inclusion of medication related information in CNMOs using a large sample of CNMOs placed at a mid-Atlantic hospital system in 2017, and via interviews with physicians. The study found that more than 42% of CNMOs contain medication related information. Moreover, the use of CNMOs varied significantly across provider types, hospital locations, patient settings and other factors. The study found 10 themes that might cause providers to adopt such workarounds, including missing functionality and poor usability. The viii study also identified several general challenges in communicating medication information in the EHR, and potential solutions to mitigate these challenges. This dissertation also demonstrates how natural language processing could be used to identify medication related CNMOs

Hitzen arteko antzekotasuna:ezagutza-baseetan oinarritutako tekniken ekarpenak

146 p.Eredu konputazionalekin sortutako hitzen errepresentazio semantikoak gakoa dira hizkuntzarenprozesamenduko hainbat atazatan, eta errepresentazio horien kalitatea ebaluatzeko hitzen artekoantzekotasuna erabiltzen da. Antzekotasun-ataza hizkuntzaren prozesamenduaren alorrean kokatzen da,lexiko-semantikan, eta, hurrengo urratsak ditu: lehenik, hitzen arteko antzekotasuna hitzenerrepresentazioen bidez kalkulatzen da; ondoren, antzekotasun hori gizakien antzekotasun-irizpideekinkonparatzen da. Eredu konputazionalaren emaitzak zenbat eta gizakion irizpideetatik hurbilago egon, orduaneta kalitate hobea izango dute hitzen errepresentazioek. Lan honetan antzekotasunaren kasuorokorragoarekin ere lan egin dugu, ahaidetasunarekin.Hitzen errepresentazioan testu-corpusetan oinarritutako metodoak eta ezagutza-baseetan oinarritutakoakdaude. Aurreneko familian hainbat eredu daude, baina, lan honetan neurona-sareetan oinarritutakoak erabiliditugu. Metodo horiek hitzen esanahiak testuetako hitz-testuinguru agerkidetzen bidez inferitzen dituzte etabektore-espazio trinko batean kodetzen. Bigarren familiakoen artean, ezagutza-baseak grafoak balira bezalatratatzen dituztenez baliatu gara, azken horien informazio estrukturala bere osotasuenan ustiatuz. Aldebatetik, testu corpusetatik erauzitako errepresentazio trinkoek arrakasta handia izan dute hainbat atazatan,baina, antzekotasun- eta ahaidetasun-erlazioak nahastuta daude hitzen errepresentazioetan. Bestetik,ezagutza-baseetako errepresentazioak kalkulatzea konputazionalki garestia da, baina, ezagutza-baseetanantzekotasun- eta ahaidetasun-erlazioak esplizituak dira.Tesi-lan honen xedea antzekotasun-atazako emaitzak hobetzea da, eta, azken hori hitzen errepresentaziosemantiko hobeak erdiesteko teknikez burutuko dugu. Gure hipotesi nagusia testu-corpusetako etaezagutza-baseetako informazioa desberdina eta osagarria dela da. Gure aburuz, bi iturri horiek konbinatuzgero hitzen errepresentazioen arteko antzekotasun-emaitzak hobetuko dira, eta, ondorioz, errepresentaziohobeak izango ditugu. Hipotesi hori, gainera, elearteko erlazioetara hedatu dugu. elearteko antzekotasunaeta ahaidetasuna ere esploratuz. Izan ere, bi baliabide horiek antzekotasunaren edota ahaidetasunarennabardura desberdinak jasotzen dituzte, eta, konbinatuz gero, antzekotasuna eta ahaidetasuna hobetomodelatuko dute.Tesi-lan honen bitartez aurreko paragrafoko hipotesiak frogatu ditugu, eta egindako ekarpenak hurrengohirurak dira: (1) ausazko ibilbideen metodo batekin ezagutza-baseetako informazio estrukturala corpusbatean kodetzea, eta azken horren hitzen errepresentazio semantikoak kalkulatzea; (2) testuko etaezagutza-baseetako informazio semantikoa konbinatzeko hainbat metodo eta errepresentazio hibridoproposatzea; (3) aurretik proposatutako guztiak elearteko erlazioetan aplikatzea.Aipatuako metodo eta konbinaketa oro antzekotasun-atazan ebaluatu ditugu, beren emaitzak artearenegoerako metodo baliokideekin konparatuz. Gure proposamenek antzekotasun-atazako artearen egoeraberdindu edo gainditu dute, eta gure hipotesiak betetzen direla ondorioztatu dugu

Hitzen arteko antzekotasuna:ezagutza-baseetan oinarritutako tekniken ekarpenak

146 p.Eredu konputazionalekin sortutako hitzen errepresentazio semantikoak gakoa dira hizkuntzarenprozesamenduko hainbat atazatan, eta errepresentazio horien kalitatea ebaluatzeko hitzen artekoantzekotasuna erabiltzen da. Antzekotasun-ataza hizkuntzaren prozesamenduaren alorrean kokatzen da,lexiko-semantikan, eta, hurrengo urratsak ditu: lehenik, hitzen arteko antzekotasuna hitzenerrepresentazioen bidez kalkulatzen da; ondoren, antzekotasun hori gizakien antzekotasun-irizpideekinkonparatzen da. Eredu konputazionalaren emaitzak zenbat eta gizakion irizpideetatik hurbilago egon, orduaneta kalitate hobea izango dute hitzen errepresentazioek. Lan honetan antzekotasunaren kasuorokorragoarekin ere lan egin dugu, ahaidetasunarekin.Hitzen errepresentazioan testu-corpusetan oinarritutako metodoak eta ezagutza-baseetan oinarritutakoakdaude. Aurreneko familian hainbat eredu daude, baina, lan honetan neurona-sareetan oinarritutakoak erabiliditugu. Metodo horiek hitzen esanahiak testuetako hitz-testuinguru agerkidetzen bidez inferitzen dituzte etabektore-espazio trinko batean kodetzen. Bigarren familiakoen artean, ezagutza-baseak grafoak balira bezalatratatzen dituztenez baliatu gara, azken horien informazio estrukturala bere osotasuenan ustiatuz. Aldebatetik, testu corpusetatik erauzitako errepresentazio trinkoek arrakasta handia izan dute hainbat atazatan,baina, antzekotasun- eta ahaidetasun-erlazioak nahastuta daude hitzen errepresentazioetan. Bestetik,ezagutza-baseetako errepresentazioak kalkulatzea konputazionalki garestia da, baina, ezagutza-baseetanantzekotasun- eta ahaidetasun-erlazioak esplizituak dira.Tesi-lan honen xedea antzekotasun-atazako emaitzak hobetzea da, eta, azken hori hitzen errepresentaziosemantiko hobeak erdiesteko teknikez burutuko dugu. Gure hipotesi nagusia testu-corpusetako etaezagutza-baseetako informazioa desberdina eta osagarria dela da. Gure aburuz, bi iturri horiek konbinatuzgero hitzen errepresentazioen arteko antzekotasun-emaitzak hobetuko dira, eta, ondorioz, errepresentaziohobeak izango ditugu. Hipotesi hori, gainera, elearteko erlazioetara hedatu dugu. elearteko antzekotasunaeta ahaidetasuna ere esploratuz. Izan ere, bi baliabide horiek antzekotasunaren edota ahaidetasunarennabardura desberdinak jasotzen dituzte, eta, konbinatuz gero, antzekotasuna eta ahaidetasuna hobetomodelatuko dute.Tesi-lan honen bitartez aurreko paragrafoko hipotesiak frogatu ditugu, eta egindako ekarpenak hurrengohirurak dira: (1) ausazko ibilbideen metodo batekin ezagutza-baseetako informazio estrukturala corpusbatean kodetzea, eta azken horren hitzen errepresentazio semantikoak kalkulatzea; (2) testuko etaezagutza-baseetako informazio semantikoa konbinatzeko hainbat metodo eta errepresentazio hibridoproposatzea; (3) aurretik proposatutako guztiak elearteko erlazioetan aplikatzea.Aipatuako metodo eta konbinaketa oro antzekotasun-atazan ebaluatu ditugu, beren emaitzak artearenegoerako metodo baliokideekin konparatuz. Gure proposamenek antzekotasun-atazako artearen egoeraberdindu edo gainditu dute, eta gure hipotesiak betetzen direla ondorioztatu dugu

A cross-linguistic study of the lexis of locomotion in learners of second language English

The lexical development of second language learners can be seen to involve them in a process of recategorization. This is also a lifelong, though progressively attenuated, feature in the first language. For the second language learner, however, the process is complicated by the possibility of lexico-semantic interaction between the first and later languages learned.The lexical focus of the study is on the semantic domain of locomotion, which is seen in cognitive semantic terms as a realization of the Source-PathGoal schema. Talmy's typology of motion events provides the linguistic framework for the research programme. According to this typology, languages will tend to have a characteristic verb lexicalization pattern in which motion is conflated with either a Path or a Manner component.The language-learning context is one of learners of English as a second language in a multilingual African country - Kenya. The subjects in the study were drawn from three different first language communities — Luo, Nandi and Lunyore — the first two being Nilotic languages and the third a Bantu language. There were also two levels of L2 proficiency - intermediate and advanced.Four tasks were used to investigate the mental lexicon of the subjects in order to clarify the role of the Ll in lexical organization and use. Two tasks, involving story retelling and sentence completion, considered productive lexical usage and two, using sentence judging and card sorting, looked at receptive usage. Individual verb use was examined as well as Talmy's typology.The results support the view that the mother tongue does influence L2 vocabulary use, both receptive and productive, in quite subtle ways, such as lexicalization patterns, frequency of use of particular verbs, the understanding and acceptance of certain verbs. The influence will vary according to the nature of the task and between individuals. It also tends to decline with greater proficiency, although an established local variety of the L2 is likely to reinforce certain features

The healthy organisation: is it meaningful?

In the thesis we have defined what is understood as a high health organization, and this in comparison with what is commonly known as a high performance organization. While much research is undertaken around high performance organizations, little or no research is undertaken around high health organizations. The thesis attempts to find answers to what it takes to be or to become a high health organization, and how organizations could create such a place, or possibly better “space”. Indeed, a high health organization is not a place, a building, or on organizational structure; it is a state of mind, a purpose, a form of coherence. The work in this thesis is by definition multidisciplinary and systemic, rooted in three, for the purpose, complementary research areas. Workplace spirituality is slowly making its recognition in the management literature, though still too much as a discipline in itself. Ayurveda, the thousands of years old wisdom tradition around systemic health, living systems and purposefulness does get some attention in academic work, however mainly within its cultural roots (of India). Finally, systemic thinking, not really mainstream yet either, is a scientific discipline that did find its way in the sciences, but is much less popular and use in management studies. As argued, we think that in the intersection of workplace spirituality, Ayurveda and systemics, a real new concept of a high health organization is emerging. Key concepts identified in the introduction were consciousness and coherence, which they play an important role in the entire thesis. The prevailing management research is based on an ontology of materialism, while it is clear that workplace spirituality, Ayurveda and systemics do not necessarily fit such an ontology. We have commented on an ontology of non-materialism, based on complexity theory and in particular the understanding of complex adaptive systems. If we would like to explore the concept of a high health organization, an adequate ontology (and epistemology) is necessary. It is impossible to develop a non-materialistic concepts within a materialistic ontology. The consequence of this ontological choice for our research methods are multiple and innovative. Our research method goes beyond deterministic causality, and attempts to visualize entanglement. It can only be based on a much more systemic analysis than what we are used to, hence we use Artificial Neural Networks and Semantics as analytical tools. Based on the results of our field research, the high health organization in a nutshell has the following components: 1. A systemic, values-based vision is the lighthouse of the high health organization 2. Values, and in particular lived values, are the driver of the high health organization 3. Transparent, clear, respectful and non-violent communication is the binding factor 4. A knowledge and learning culture is the necessary condition for a healthy organization 5. Organisational consciousness in the organization is the sufficient conditio

Information structure and the referential status of linguistic expression : workshop as part of the 23th annual meetings of the Deutsche Gesellschaft für Sprachwissenschaft in Leipzig, Leipzig, February 28 - March 2, 2001

This volume comprises papers that were given at the workshop Information Structure and the Referential Status of Linguistic Expressions, which we organized during the Deutsche Gesellschaft für Sprachwissenschaft (DGfS) Conference in Leipzig in February 2001. At this workshop we discussed the connection between information structure and the referential interpretation of linguistic expressions, a topic mostly neglected in current linguistics research. One common aim of the papers is to find out to what extent the focus-background as well as the topic-comment structuring determine the referential interpretation of simple arguments like definite and indefinite NPs on the one hand and sentences on the other

Signs and classrooms : historical perspectives on the role of signs in human development, with particular reference to an urban classroom

Abstract\ud The role of language in development has been a central theme in post-war English. However, the European history of ideas about the role of signs has been insufficiently appreciated. I aim to enrich readings of contemporary urban classrooms by recovering something of this history. As the culmination of this work, I trace the story of a poem, written by a Black student in a London classroom, back into the history of discussions and debates that a class conducted with itself over five years. From perspectives provided by the history of ideas and recent work in social memory, I show how the student's representation of a childhood recollection (a visit to the site of a former plantation) was mediated and shaped by 'pedagogical artefacts'. I give a history of one such artefact as an instance of the role of signs in a contemporary classroom.\ud A picture of language as human invention was drawn in the first instance during the European Enlightenment. From this picture a seminal theory about the role of signs in the mastery of mental operations emerged. On this view, memory and imagination depend upon signs. In the aftermath to the French Revolution, language was linked to conceptions of citizenship and human advancement. In Germany, the picture of language was redrawn in the light of Kant's epistemology, and connected to an educational ideal of selfcultivation.\ud In the nineteenth century, 'cultural' psychology attempted\ud unsuccessfully to combine a notion of signs in the development of higher mental functions with findings in experimental psychology. Subsequently, the introduction of a distinction between mental 'contents' and mental 'acts' fostered new research into the role of signs in consciousness. Concurrently, an ethical vision of symbolisation as the 'common ground' of humanity issued from a philosophy of symbolic forms. As a whole the thesis seeks to show the continuing relevance of this history

Can I help you? : a systemic-functional exploration of service encounter interaction

This exploratory study of the semiotic organization of service encounter interaction and its realization traces back the Malinowskian/Firthian contextual theory and follows its development into register theory. It captures the most recent developments of register theory which consider texts as organizations on three separate semiotic communication planes: genre, register and language. Specifically it focusses on how on the plane of genre the global patternings of texts, i.e. SCHEMATIC STRUCTURES, are represented and how they are realized by the planes of register and language which are seen to underlie genre. It studies and develops the notion of genre and its realization by using service encounter data