Journal of the American Medical Informatics Association, 2000
To develop a model for Bayesian communication to enable readers to make reported data more releva... more To develop a model for Bayesian communication to enable readers to make reported data more relevant by including their prior knowledge and values. Background: To change their practice, clinicians need good evidence, yet they also need to make new technology applicable to their local knowledge and circumstances. Availability of the Web has the potential for greatly affecting the scientific communication process between research and clinician. Going beyond format changes and hyperlinking, Bayesian communication enables readers to make reported data more relevant by including their prior knowledge and values. This paper addresses the needs and implications for Bayesian communication. Formulation: Literature review and development of specifications from readers', authors', publishers', and computers' perspectives consistent with formal requirements for Bayesian reasoning. Results: Seventeen specifications were developed, which included eight for readers (express prior knowledge, view effect size and variability, express threshold, make inferences, view explanation, evaluate study and statistical quality, synthesize multiple studies, and view prior beliefs of the community), three for authors (protect the author's investment, publish enough information, make authoring easy), three for publishers (limit liability, scale up, and establish a business model), and two for computers (incorporate into reading process, use familiar interface metaphors). A sample client-only prototype is available at http://omie.med.jhmi.edu/bayes. Conclusion: Bayesian communication has formal justification consistent with the needs of readers and can best be implemented in an online environment. Much research must be done to establish whether the formalism and the reality of readers' needs can meet.
Summary Objective: To develop a heuristic framework for students to organize and apply the many c... more Summary Objective: To develop a heuristic framework for students to organize and apply the many concepts of informatics for rapid use. Method: Organization of curriculum material and recurrent refinement by student feedback. An Informatics Stack was developed based on several existing informatics and software-development frameworks comprising several levels of abstraction, from what a system is supposed to accomplish (4 levels) to how it accomplishes it (5 levels). At each level, there are specific concerns, types of interoperability, ethical and legal issues, testing and evaluation approaches and methods, and relevant scientific disciplines, and privacy (upper 5 levels), confidentiality (middle 3 levels), and security (lower 4 levels ) concerns whose levels overlap. An 8-week Introduction to Informatics course was taught for 6 years to masters students of informatics and of public health, based on the Stack, with a Final Project continually filled in during the course, where studen...
Despite speculation that Telemicroscopy and Digital Microscopy will follow the same diffusion cur... more Despite speculation that Telemicroscopy and Digital Microscopy will follow the same diffusion curves as their counterparts in the world of Radiology - Teleradiology and Filmless Radiology, no study has offered definitive evidence in support of this hypothesis. To address this gap in the informatics knowledge base, dual survey instruments were created to measure current opinions on both technologies among Pathologists and Radiologists and disseminated to Pathologists and Radiologists at two major academic medical centers.
Journal of Developmental & Behavioral Pediatrics, 1990
Clinicians need to know the consistency of a child&am... more Clinicians need to know the consistency of a child's report of his pain in order to assess the intensity of that pain. To explore an age cutoff above which children are consistent in reporting their pain, we tested the consistency of children's reports of recalled pain, using a variety of scales. We interviewed 91 children, three to eight years of age, and obtained each child's report of two of his own painful experiences. In two separate sessions, we asked each child to compare those specific experiences in several ways, using two picture scales, a block-based scale, triads, and the simple question, "which hurt you more?" Results show that children older than seven years are more consistent in reporting the relative pain intensity of remembered events than younger ones (range 50-100% vs. 20-55%, p less than 0.001), and that the simple question provides the most consistent answer. However, no age group tested was consistent more than 80% of the time on all measures. We conclude that children are able to report remembered pain intensity consistently with increasing age but that we cannot establish a firm cutoff between the ages of three and eight years with our data.
JAMA: The Journal of the American Medical Association, 1997
1. JAMA. 1997 Dec 3;278(21):1788. The use of simulations in computer-aided learning over the Worl... more 1. JAMA. 1997 Dec 3;278(21):1788. The use of simulations in computer-aided learning over the World Wide Web. Lehmann HP, Lehmann CU, Freedman JA. Johns Hopkins School of Medicine, USA. PMID: 9388163 [PubMed - indexed for MEDLINE]. MeSH Terms. Computer Communication Networks*; Computer Simulation*; Computer-Assisted Instruction*; Curriculum; Education, Medical/trends*; Models, Educational*.
There is a need for multimodal strategies to keep research participants informed about study resu... more There is a need for multimodal strategies to keep research participants informed about study results. Our aim was to characterize preferences of genomic research participants from two institutions along four dimensions of general research result updates: content, timing, mechanism, and frequency. Methods: We conducted a web-based cross-sectional survey that was administered from 25 June 2018 to 5 December 2018. Results: 397 participants completed the survey, most of whom (96%) expressed a desire to receive research updates. Preferences with high endorsement included: update content (brief descriptions of major findings, descriptions of purpose and goals, and educational material); update timing (when the research is completed, when findings are reviewed, when findings are published, and when the study status changes); update mechanism (email with updates, and email newsletter); and update frequency (every three months). Hierarchical cluster analyses based on the four update preferen...
In this commentary, we work out the specific desired functions required for sharing knowledge obj... more In this commentary, we work out the specific desired functions required for sharing knowledge objects (based on statistical models) presumably to be used for clinical decision support derived from a learning health system, and, in so doing, discuss the implications for novel knowledge architectures. We will demonstrate how decision models, implemented as influence diagrams, satisfy the desiderata. The desiderata include locally validate discrimination, locally validate calibration, locally recalculate thresholds by incorporating local preferences, provide explanation, enable monitoring, enable debiasing, account for generalizability, account for semantic uncertainty, shall be findable, and others as necessary and proper. We demonstrate how formal decision models, especially when implemented as influence diagrams based on Bayesian networks, support both the knowledge artifact itself (the "primary decision") and the "meta-decision" of whether to deploy the knowledge artifact. We close with a research and development agenda to put this framework into place.
ObjectivesWomen report higher atrial fibrillation (AF) symptom severity and receive less AF thera... more ObjectivesWomen report higher atrial fibrillation (AF) symptom severity and receive less AF therapies than their male counterparts. It is understudied if differences in AF therapies received explains sex differences in AF symptom severity. We investigate the impact of sex and AF therapies on patient-reported outcomes.MethodsParticipants were recruited (n=953) across four academic medical centres with an AF diagnosis and age ≥18 years. Patient-reported outcomes (AF symptom severity, AF-related quality of life, functional status and emotional status) were determined by biannual surveys. We performed multiple linear regressions on propensity-matched cohorts to determine the association of AF therapies and sex on patient-reported outcomes.ResultsOur study population (n=953) was 65% male (n=616), 93% white (n=890) and 72 (±10) years old. Individuals receiving rate control therapy reported comparatively lower AF-related quality of life (−7.22, 95% CI −11.51 to –2.92) and poorer functional...
STUDY OBJECTIVE To compare clinician perspectives for the treatment of pelvic inflammatory diseas... more STUDY OBJECTIVE To compare clinician perspectives for the treatment of pelvic inflammatory disease (PID) with those of adolescent patients and parents. DESIGN Cross-sectional study. SETTING Urban academic pediatric and adolescent medicine practices and school-based health clinics in a large urban community with a high prevalence of sexually transmitted infections and a national sample of adolescent-serving clinicians. PARTICIPANTS Female patients aged 12-19 years, parents raising an adolescent older than the age of 12 years in the urban community, and clinicians who serve adolescents recruited from regional and national listservs. INTERVENTIONS None. MAIN OUTCOME MEASURES Visual analogue scale scores on a scale of 0-10 corresponding to preferences on patient disposition in 17 clinical scenarios for a hypothetical patient with PID. RESULTS Compared with adolescents, clinicians were significantly more likely to endorse hospitalizations when patients presented with severe or complicated illness (β = 0.9; standard error [SE], 0.22; P < .001), possible surgical emergency (β = 0.83; SE, 0.2; P < .001), concurrent pregnancy (β = 0.59; SE, 0.3; P = .046), or failure of outpatient treatment (β = 0.58; SE, 0.29; P = .045). Compared with clinicians, adolescents were significantly more likely to endorse hospitalizations when patients presented at a young age (β = 1.36; SE, 0.38; P < .001), were homeless (β = 0.88; SE, 0.32; P = .007), were afraid to inform a partner (β = 1.66; SE, 0.40; P < .001), or had unaware parents (β = 2.86; SE, 0.39; P < .001). CONCLUSION Clinicians were more likely to recommend hospitalization when doing so adhered to national guidelines on PID treatment. Adolescents opted for hospitalization more often than clinicians in scenarios in which patients exhibited social vulnerability. Clinicians should engage with adolescents in shared disposition planning and use a more nuanced approach to PID management for adolescents who might not be able to tolerate an outpatient regimen.
Background Inhospital pediatric trauma care typically spans multiple locations, which influences ... more Background Inhospital pediatric trauma care typically spans multiple locations, which influences the use of resources, that could be improved by gaining a better understanding of the inhospital flow of patients and identifying opportunities for improvement. Objectives To describe a process mining approach for mapping the inhospital flow of pediatric trauma patients, to identify and characterize the major patient pathways and care transitions, and to identify opportunities for patient flow and triage improvement. Methods From the trauma registry of a level I pediatric trauma center, data were extracted regarding the two highest trauma activation levels, Alpha (n = 228) and Bravo (n = 1,713). An event log was generated from the admission, discharge, and transfer data from which patient pathways and care transitions were identified and described. The Flexible Heuristics Miner algorithm was used to generate a process map for the cohort, and separate process maps for Alpha and Bravo enco...
Background Electronic health record (EHR) systems contain large volumes of novel heterogeneous da... more Background Electronic health record (EHR) systems contain large volumes of novel heterogeneous data that can be linked to trauma registry data to enable innovative research not possible with either data source alone. Objective This article describes an approach for linking electronically extracted EHR data to trauma registry data at the institutional level and assesses the value of probabilistic linkage. Methods Encounter data were independently obtained from the EHR data warehouse (n = 1,632) and the pediatric trauma registry (n = 1,829) at a Level I pediatric trauma center. Deterministic linkage was attempted using nine different combinations of medical record number (MRN), encounter identity (ID) (visit ID), age, gender, and emergency department (ED) arrival date. True matches from the best performing variable combination were used to create a gold standard, which was used to evaluate the performance of each variable combination, and to train a probabilistic algorithm that was se...
Electronic Medical Records (EMRs) are the obvious source for providing case material for learners... more Electronic Medical Records (EMRs) are the obvious source for providing case material for learners. Cases will be identified by clinician authors, and will be adopted or redacted by clinical teachers for use in multiple types of computer-based learning environments: case presentation, simulation, and management.
Background:Decision analysis (DA) can assess optimal management strategies when there are insuffi... more Background:Decision analysis (DA) can assess optimal management strategies when there are insufficient data from clinical trials to guide clinical decision-making. The validity of DA has not been studied. We identified decision analyses on infectious diseases (ID) topics and compared them to clinical studies that were published after the decision analysis. Methods: A search for ID-related DA published from1990-2005 was performed using PubMed. Articles that met the search criteria had major MeSH headings pertaining to decision analysis or “decision analysis” as a text word in the abstract or title, and MeSH terms pertaining to ID. Abstracts of all identified articles were reviewed and confirmed ID-related DA were retained. Subsequent clinical trials and observational studies that corresponded to these DA were identified using: 1) a PubMed related articles search limited to clinical trials; 2) an ISI Web of Science citation and related articles search; and 3) a topic search of the Coc...
Managing cultures taken from patients in a teaching outpatient setting, such as Johns Hopkins Har... more Managing cultures taken from patients in a teaching outpatient setting, such as Johns Hopkins Harriet Lane Clinic (HLC) in Baltimore, is a complicated task to model,because it must support a task that lasts several days. There are many considerations in replacing the paper based system currently in place. We needed to balance the need for speed with the recognizability of familiar forms; the need for quality care with the need for teaching;and the need for documentation with the need for compact representation of clinical need.
Influence diagrams are ideal knowledge representations for Bayesian statistical models. However, ... more Influence diagrams are ideal knowledge representations for Bayesian statistical models. However, these diagrams are difficult for end users to interpret and to manipulate. We present a user-based architecture that enables end users to create and to manipulate the knowledge representation. We use the problem of physicians' interpretation of two-arm parallel randomized clinical trials (T APRCT) to illustrate the architecture and its use. There are three primary data structures. Elements of statistical models are encoded as subgraphs of a restricted class of influence diagram. The interpretations of those elements are mapped into users' language in a domain-specific, user-based semantic interface, called a patient-flow diagram, in the T APRCT problem. Pennitted transformations of the statistical model that maintain the semantic relationships of the model are encoded in a metadata-state diagram, called the cohort-state diagram, in the T APRCT problem. The algorithm that runs the system uses modular actions called construction steps. This framework has been implemented in a system called THOMAS, that allows physicians to interpret the data reported from a T APR CT.
Physicians burdened with increasing paper work may find relief in computer-based patient records ... more Physicians burdened with increasing paper work may find relief in computer-based patient records (CPR). CPRs may aid clinicians in the areas of billing, documentation, reporting, and data retrieval. Value-added features like decision support and event monitoring facilitate patient outcome, decrease health care costs and allow improved administration. The authors discuss obstacles in the use of computers in patient care with a focus on security, confidentiality, and Y2K.
AMIA Joint Summits on Translational Science proceedings AMIA Summit on Translational Science, 2010
Human studies, encompassing interventional and observational studies, are the most important sour... more Human studies, encompassing interventional and observational studies, are the most important source of evidence for advancing our understanding of health, disease, and treatment options. To promote discovery, the design and results of these studies should be made machine-readable for large-scale data mining, synthesis, and re-analysis. The Human Studies Database Project aims to define and implement an informatics infrastructure for institutions to share the design of their human studies. We have developed the Ontology of Clinical Research (OCRe) to model study features such as design type, interventions, and outcomes to support scientific query and analysis. We are using OCRe as the reference semantics for federated data sharing of human studies over caGrid, and are piloting this implementation with several Clinical and Translational Science Award (CTSA) institutions.
Journal of the American Medical Informatics Association, 2000
To develop a model for Bayesian communication to enable readers to make reported data more releva... more To develop a model for Bayesian communication to enable readers to make reported data more relevant by including their prior knowledge and values. Background: To change their practice, clinicians need good evidence, yet they also need to make new technology applicable to their local knowledge and circumstances. Availability of the Web has the potential for greatly affecting the scientific communication process between research and clinician. Going beyond format changes and hyperlinking, Bayesian communication enables readers to make reported data more relevant by including their prior knowledge and values. This paper addresses the needs and implications for Bayesian communication. Formulation: Literature review and development of specifications from readers', authors', publishers', and computers' perspectives consistent with formal requirements for Bayesian reasoning. Results: Seventeen specifications were developed, which included eight for readers (express prior knowledge, view effect size and variability, express threshold, make inferences, view explanation, evaluate study and statistical quality, synthesize multiple studies, and view prior beliefs of the community), three for authors (protect the author's investment, publish enough information, make authoring easy), three for publishers (limit liability, scale up, and establish a business model), and two for computers (incorporate into reading process, use familiar interface metaphors). A sample client-only prototype is available at http://omie.med.jhmi.edu/bayes. Conclusion: Bayesian communication has formal justification consistent with the needs of readers and can best be implemented in an online environment. Much research must be done to establish whether the formalism and the reality of readers' needs can meet.
Summary Objective: To develop a heuristic framework for students to organize and apply the many c... more Summary Objective: To develop a heuristic framework for students to organize and apply the many concepts of informatics for rapid use. Method: Organization of curriculum material and recurrent refinement by student feedback. An Informatics Stack was developed based on several existing informatics and software-development frameworks comprising several levels of abstraction, from what a system is supposed to accomplish (4 levels) to how it accomplishes it (5 levels). At each level, there are specific concerns, types of interoperability, ethical and legal issues, testing and evaluation approaches and methods, and relevant scientific disciplines, and privacy (upper 5 levels), confidentiality (middle 3 levels), and security (lower 4 levels ) concerns whose levels overlap. An 8-week Introduction to Informatics course was taught for 6 years to masters students of informatics and of public health, based on the Stack, with a Final Project continually filled in during the course, where studen...
Despite speculation that Telemicroscopy and Digital Microscopy will follow the same diffusion cur... more Despite speculation that Telemicroscopy and Digital Microscopy will follow the same diffusion curves as their counterparts in the world of Radiology - Teleradiology and Filmless Radiology, no study has offered definitive evidence in support of this hypothesis. To address this gap in the informatics knowledge base, dual survey instruments were created to measure current opinions on both technologies among Pathologists and Radiologists and disseminated to Pathologists and Radiologists at two major academic medical centers.
Journal of Developmental & Behavioral Pediatrics, 1990
Clinicians need to know the consistency of a child&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;am... more Clinicians need to know the consistency of a child&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s report of his pain in order to assess the intensity of that pain. To explore an age cutoff above which children are consistent in reporting their pain, we tested the consistency of children&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s reports of recalled pain, using a variety of scales. We interviewed 91 children, three to eight years of age, and obtained each child&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s report of two of his own painful experiences. In two separate sessions, we asked each child to compare those specific experiences in several ways, using two picture scales, a block-based scale, triads, and the simple question, &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;which hurt you more?&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; Results show that children older than seven years are more consistent in reporting the relative pain intensity of remembered events than younger ones (range 50-100% vs. 20-55%, p less than 0.001), and that the simple question provides the most consistent answer. However, no age group tested was consistent more than 80% of the time on all measures. We conclude that children are able to report remembered pain intensity consistently with increasing age but that we cannot establish a firm cutoff between the ages of three and eight years with our data.
JAMA: The Journal of the American Medical Association, 1997
1. JAMA. 1997 Dec 3;278(21):1788. The use of simulations in computer-aided learning over the Worl... more 1. JAMA. 1997 Dec 3;278(21):1788. The use of simulations in computer-aided learning over the World Wide Web. Lehmann HP, Lehmann CU, Freedman JA. Johns Hopkins School of Medicine, USA. PMID: 9388163 [PubMed - indexed for MEDLINE]. MeSH Terms. Computer Communication Networks*; Computer Simulation*; Computer-Assisted Instruction*; Curriculum; Education, Medical/trends*; Models, Educational*.
There is a need for multimodal strategies to keep research participants informed about study resu... more There is a need for multimodal strategies to keep research participants informed about study results. Our aim was to characterize preferences of genomic research participants from two institutions along four dimensions of general research result updates: content, timing, mechanism, and frequency. Methods: We conducted a web-based cross-sectional survey that was administered from 25 June 2018 to 5 December 2018. Results: 397 participants completed the survey, most of whom (96%) expressed a desire to receive research updates. Preferences with high endorsement included: update content (brief descriptions of major findings, descriptions of purpose and goals, and educational material); update timing (when the research is completed, when findings are reviewed, when findings are published, and when the study status changes); update mechanism (email with updates, and email newsletter); and update frequency (every three months). Hierarchical cluster analyses based on the four update preferen...
In this commentary, we work out the specific desired functions required for sharing knowledge obj... more In this commentary, we work out the specific desired functions required for sharing knowledge objects (based on statistical models) presumably to be used for clinical decision support derived from a learning health system, and, in so doing, discuss the implications for novel knowledge architectures. We will demonstrate how decision models, implemented as influence diagrams, satisfy the desiderata. The desiderata include locally validate discrimination, locally validate calibration, locally recalculate thresholds by incorporating local preferences, provide explanation, enable monitoring, enable debiasing, account for generalizability, account for semantic uncertainty, shall be findable, and others as necessary and proper. We demonstrate how formal decision models, especially when implemented as influence diagrams based on Bayesian networks, support both the knowledge artifact itself (the "primary decision") and the "meta-decision" of whether to deploy the knowledge artifact. We close with a research and development agenda to put this framework into place.
ObjectivesWomen report higher atrial fibrillation (AF) symptom severity and receive less AF thera... more ObjectivesWomen report higher atrial fibrillation (AF) symptom severity and receive less AF therapies than their male counterparts. It is understudied if differences in AF therapies received explains sex differences in AF symptom severity. We investigate the impact of sex and AF therapies on patient-reported outcomes.MethodsParticipants were recruited (n=953) across four academic medical centres with an AF diagnosis and age ≥18 years. Patient-reported outcomes (AF symptom severity, AF-related quality of life, functional status and emotional status) were determined by biannual surveys. We performed multiple linear regressions on propensity-matched cohorts to determine the association of AF therapies and sex on patient-reported outcomes.ResultsOur study population (n=953) was 65% male (n=616), 93% white (n=890) and 72 (±10) years old. Individuals receiving rate control therapy reported comparatively lower AF-related quality of life (−7.22, 95% CI −11.51 to –2.92) and poorer functional...
STUDY OBJECTIVE To compare clinician perspectives for the treatment of pelvic inflammatory diseas... more STUDY OBJECTIVE To compare clinician perspectives for the treatment of pelvic inflammatory disease (PID) with those of adolescent patients and parents. DESIGN Cross-sectional study. SETTING Urban academic pediatric and adolescent medicine practices and school-based health clinics in a large urban community with a high prevalence of sexually transmitted infections and a national sample of adolescent-serving clinicians. PARTICIPANTS Female patients aged 12-19 years, parents raising an adolescent older than the age of 12 years in the urban community, and clinicians who serve adolescents recruited from regional and national listservs. INTERVENTIONS None. MAIN OUTCOME MEASURES Visual analogue scale scores on a scale of 0-10 corresponding to preferences on patient disposition in 17 clinical scenarios for a hypothetical patient with PID. RESULTS Compared with adolescents, clinicians were significantly more likely to endorse hospitalizations when patients presented with severe or complicated illness (β = 0.9; standard error [SE], 0.22; P < .001), possible surgical emergency (β = 0.83; SE, 0.2; P < .001), concurrent pregnancy (β = 0.59; SE, 0.3; P = .046), or failure of outpatient treatment (β = 0.58; SE, 0.29; P = .045). Compared with clinicians, adolescents were significantly more likely to endorse hospitalizations when patients presented at a young age (β = 1.36; SE, 0.38; P < .001), were homeless (β = 0.88; SE, 0.32; P = .007), were afraid to inform a partner (β = 1.66; SE, 0.40; P < .001), or had unaware parents (β = 2.86; SE, 0.39; P < .001). CONCLUSION Clinicians were more likely to recommend hospitalization when doing so adhered to national guidelines on PID treatment. Adolescents opted for hospitalization more often than clinicians in scenarios in which patients exhibited social vulnerability. Clinicians should engage with adolescents in shared disposition planning and use a more nuanced approach to PID management for adolescents who might not be able to tolerate an outpatient regimen.
Background Inhospital pediatric trauma care typically spans multiple locations, which influences ... more Background Inhospital pediatric trauma care typically spans multiple locations, which influences the use of resources, that could be improved by gaining a better understanding of the inhospital flow of patients and identifying opportunities for improvement. Objectives To describe a process mining approach for mapping the inhospital flow of pediatric trauma patients, to identify and characterize the major patient pathways and care transitions, and to identify opportunities for patient flow and triage improvement. Methods From the trauma registry of a level I pediatric trauma center, data were extracted regarding the two highest trauma activation levels, Alpha (n = 228) and Bravo (n = 1,713). An event log was generated from the admission, discharge, and transfer data from which patient pathways and care transitions were identified and described. The Flexible Heuristics Miner algorithm was used to generate a process map for the cohort, and separate process maps for Alpha and Bravo enco...
Background Electronic health record (EHR) systems contain large volumes of novel heterogeneous da... more Background Electronic health record (EHR) systems contain large volumes of novel heterogeneous data that can be linked to trauma registry data to enable innovative research not possible with either data source alone. Objective This article describes an approach for linking electronically extracted EHR data to trauma registry data at the institutional level and assesses the value of probabilistic linkage. Methods Encounter data were independently obtained from the EHR data warehouse (n = 1,632) and the pediatric trauma registry (n = 1,829) at a Level I pediatric trauma center. Deterministic linkage was attempted using nine different combinations of medical record number (MRN), encounter identity (ID) (visit ID), age, gender, and emergency department (ED) arrival date. True matches from the best performing variable combination were used to create a gold standard, which was used to evaluate the performance of each variable combination, and to train a probabilistic algorithm that was se...
Electronic Medical Records (EMRs) are the obvious source for providing case material for learners... more Electronic Medical Records (EMRs) are the obvious source for providing case material for learners. Cases will be identified by clinician authors, and will be adopted or redacted by clinical teachers for use in multiple types of computer-based learning environments: case presentation, simulation, and management.
Background:Decision analysis (DA) can assess optimal management strategies when there are insuffi... more Background:Decision analysis (DA) can assess optimal management strategies when there are insufficient data from clinical trials to guide clinical decision-making. The validity of DA has not been studied. We identified decision analyses on infectious diseases (ID) topics and compared them to clinical studies that were published after the decision analysis. Methods: A search for ID-related DA published from1990-2005 was performed using PubMed. Articles that met the search criteria had major MeSH headings pertaining to decision analysis or “decision analysis” as a text word in the abstract or title, and MeSH terms pertaining to ID. Abstracts of all identified articles were reviewed and confirmed ID-related DA were retained. Subsequent clinical trials and observational studies that corresponded to these DA were identified using: 1) a PubMed related articles search limited to clinical trials; 2) an ISI Web of Science citation and related articles search; and 3) a topic search of the Coc...
Managing cultures taken from patients in a teaching outpatient setting, such as Johns Hopkins Har... more Managing cultures taken from patients in a teaching outpatient setting, such as Johns Hopkins Harriet Lane Clinic (HLC) in Baltimore, is a complicated task to model,because it must support a task that lasts several days. There are many considerations in replacing the paper based system currently in place. We needed to balance the need for speed with the recognizability of familiar forms; the need for quality care with the need for teaching;and the need for documentation with the need for compact representation of clinical need.
Influence diagrams are ideal knowledge representations for Bayesian statistical models. However, ... more Influence diagrams are ideal knowledge representations for Bayesian statistical models. However, these diagrams are difficult for end users to interpret and to manipulate. We present a user-based architecture that enables end users to create and to manipulate the knowledge representation. We use the problem of physicians' interpretation of two-arm parallel randomized clinical trials (T APRCT) to illustrate the architecture and its use. There are three primary data structures. Elements of statistical models are encoded as subgraphs of a restricted class of influence diagram. The interpretations of those elements are mapped into users' language in a domain-specific, user-based semantic interface, called a patient-flow diagram, in the T APRCT problem. Pennitted transformations of the statistical model that maintain the semantic relationships of the model are encoded in a metadata-state diagram, called the cohort-state diagram, in the T APRCT problem. The algorithm that runs the system uses modular actions called construction steps. This framework has been implemented in a system called THOMAS, that allows physicians to interpret the data reported from a T APR CT.
Physicians burdened with increasing paper work may find relief in computer-based patient records ... more Physicians burdened with increasing paper work may find relief in computer-based patient records (CPR). CPRs may aid clinicians in the areas of billing, documentation, reporting, and data retrieval. Value-added features like decision support and event monitoring facilitate patient outcome, decrease health care costs and allow improved administration. The authors discuss obstacles in the use of computers in patient care with a focus on security, confidentiality, and Y2K.
AMIA Joint Summits on Translational Science proceedings AMIA Summit on Translational Science, 2010
Human studies, encompassing interventional and observational studies, are the most important sour... more Human studies, encompassing interventional and observational studies, are the most important source of evidence for advancing our understanding of health, disease, and treatment options. To promote discovery, the design and results of these studies should be made machine-readable for large-scale data mining, synthesis, and re-analysis. The Human Studies Database Project aims to define and implement an informatics infrastructure for institutions to share the design of their human studies. We have developed the Ontology of Clinical Research (OCRe) to model study features such as design type, interventions, and outcomes to support scientific query and analysis. We are using OCRe as the reference semantics for federated data sharing of human studies over caGrid, and are piloting this implementation with several Clinical and Translational Science Award (CTSA) institutions.
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Papers by Harold Lehmann