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118


Extracting temporal constraints from clinical research eligibility criteria using conditional random fields

Luo, Zhihui; Johnson, Stephen B; Lai, Albert M; Weng, Chunhua
Temporal constraints are present in 38% of clinical research eligibility criteria and are crucial for screening patients. However, eligibility criteria are often written as free text, which is not amenable for computer processing. In this paper, we present an ontology-based approach to extracting temporal information from clinical research eligibility criteria. We generated temporal labels using a frame-based temporal ontology. We manually annotated 150 free-text eligibility criteria using the temporal labels and trained a parser using Conditional Random Fields (CRFs) to automatically extract temporal expressions from eligibility criteria. An evaluation of an additional 60 randomly selected eligibility criteria using manual review achieved an overall precision of 83%, a recall of 79%, and an F-score of 80%. We illustrate the application of temporal extraction with the use cases of question answering and free-text criteria querying.
PMCID:3243135
PMID: 22195142
ISSN: 1942-597x
CID: 3586452

Semi-Automatically Inducing Semantic Classes of Clinical Research Eligibility Criteria Using UMLS and Hierarchical Clustering

Luo, Zhihui; Johnson, Stephen B; Weng, Chunhua
This paper presents a novel approach to learning semantic classes of clinical research eligibility criteria. It uses the UMLS Semantic Types to represent semantic features and the Hierarchical Clustering method to group similar eligibility criteria. By establishing a gold standard using two independent raters, we evaluated the coverage and accuracy of the induced semantic classes. On 2,718 random eligibility criteria sentences, the inter-rater classification agreement was 85.73%. In a 10-fold validation test, the average Precision, Recall and F-score of the classification results of a decision-tree classifier were 87.8%, 88.0%, and 87.7% respectively. Our induced classes well aligned with 16 out of 17 eligibility criteria classes defined by the BRIDGE model. We discuss the potential of this method and our future work.
PMCID:3041461
PMID: 21347026
ISSN: 1942-597x
CID: 3586402

Using global unique identifiers to link autism collections

Johnson, Stephen B; Whitney, Glen; McAuliffe, Matthew; Wang, Hailong; McCreedy, Evan; Rozenblit, Leon; Evans, Clark C
OBJECTIVE:To propose a centralized method for generating global unique identifiers to link collections of research data and specimens. DESIGN/METHODS:The work is a collaboration between the Simons Foundation Autism Research Initiative and the National Database for Autism Research. The system is implemented as a web service: an investigator inputs identifying information about a participant into a client application and sends encrypted information to a server application, which returns a generated global unique identifier. The authors evaluated the system using a volume test of one million simulated individuals and a field test on 2000 families (over 8000 individual participants) in an autism study. MEASUREMENTS/METHODS:Inverse probability of hash codes; rate of false identity of two individuals; rate of false split of single individual; percentage of subjects for which identifying information could be collected; percentage of hash codes generated successfully. RESULTS:Large-volume simulation generated no false splits or false identity. Field testing in the Simons Foundation Autism Research Initiative Simplex Collection produced identifiers for 96% of children in the study and 77% of parents. On average, four out of five hash codes per subject were generated perfectly (only one perfect hash is required for subsequent matching). DISCUSSION/CONCLUSIONS:The system must achieve balance among the competing goals of distinguishing individuals, collecting accurate information for matching, and protecting confidentiality. Considerable effort is required to obtain approval from institutional review boards, obtain consent from participants, and to achieve compliance from sites during a multicenter study. CONCLUSION/CONCLUSIONS:Generic unique identifiers have the potential to link collections of research data, augment the amount and types of data available for individuals, support detection of overlap between collections, and facilitate replication of research findings.
PMCID:3000750
PMID: 20962132
ISSN: 1527-974x
CID: 3586392

Improving Clinical Trial Participant Tracking Tools Using Knowledge-anchored Design Methodologies

Payne, Philip R O; Embi, Peter J; Johnson, Stephen B; Mendonca, Eneida; Starren, Justin
OBJECTIVE: Rigorous human-computer interaction (HCI) design methodologies have not traditionally been applied to the development of clinical trial participant tracking (CTPT) tools. Given the frequent us of iconic HCI models in CTPTs, and prior evidence of usability problems associated with the use of ambiguous icons in complex interfaces, such approaches may be problematic. Presentation Discovery (PD), a knowledge-anchored HCI design method, has been previously demonstrated to improve the design of iconic HCI models. In this study, we compare the usability of a CTPT HCI model designed using PD and an intuitively designed CTPT HCI model. METHODS: An iconic CPTP HCI model was created using PD. The PD-generated and an existing iconic CTPT HCI model were subjected to usability testing, with an emphasis on task accuracy and completion times. Study participants also completed a qualitative survey instrument to evaluate subjective satisfaction with the two models. RESULTS: CTPT end-users reliably and reproducibly agreed on the visual manifestation and semantics of prototype graphics generated using PD. The performance of the PD-generated iconic HCI model was equivalent to an existing HCI model for tasks at multiple levels of complexity, and in some cases superior. This difference was particularly notable when tasks required an understanding of the semantic meanings of multiple icons. CONCLUSION: The use of PD to design an iconic CTPT HCI model generated beneficial results and improved end-user subjective satisfaction, while reducing task completion time. Such results are desirable in information and time intensive domains, such as clinical trials management.
PMCID:3225206
PMID: 22132037
ISSN: 1869-0327
CID: 3586442

Development and evaluation of nursing user interface screens using multiple methods

Hyun, Sookyung; Johnson, Stephen B; Stetson, Peter D; Bakken, Suzanne
Building upon the foundation of the Structured Narrative Electronic Health Record (EHR) model, we applied theory-based (combined Technology Acceptance Model and Task-Technology Fit Model) and user-centered methods to explore nurses' perceptions of functional requirements for an electronic nursing documentation system, design user interface screens reflective of the nurses' perspectives, and assess nurses' perceptions of the usability of the prototype user interface screens. The methods resulted in user interface screens that were perceived to be easy to use, potentially useful, and well-matched to nursing documentation tasks associated with Nursing Admission Assessment, Blood Administration, and Nursing Discharge Summary. The methods applied in this research may serve as a guide for others wishing to implement user-centered processes to develop or extend EHR systems. In addition, some of the insights obtained in this study may be informative to the development of safe and efficient user interface screens for nursing document templates in EHRs.
PMCID:2803697
PMID: 19460464
ISSN: 1532-0480
CID: 3586352

Evaluation of a prototype search and visualization system for exploring scientific communities

Bales, Michael E; Kaufman, David R; Johnson, Stephen B
Searches of bibliographic databases generate lists of articles but do little to reveal connections between authors, institutions, and grants. As a result, search results cannot be fully leveraged. To address this problem we developed Sciologer, a prototype search and visualization system. Sciologer presents the results of any PubMed query as an interactive network diagram of the above elements. We conducted a cognitive evaluation with six neuroscience and six obesity researchers. Researchers used the system effectively. They used geographic, color, and shape metaphors to describe community structure and made accurate inferences pertaining to a) collaboration among research groups; b) prominence of individual researchers; and c) differentiation of expertise. The tool confirmed certain beliefs, disconfirmed others, and extended their understanding of their own discipline. The majority indicated the system offered information of value beyond a traditional PubMed search and that they would use the tool if available.
PMCID:2815483
PMID: 20351816
ISSN: 1942-597x
CID: 3586382

Synergies and distinctions between computational disciplines in biomedical research: perspective from the Clinical andTranslational Science Award programs

Bernstam, Elmer V; Hersh, William R; Johnson, Stephen B; Chute, Christopher G; Nguyen, Hien; Sim, Ida; Nahm, Meredith; Weiner, Mark G; Miller, Perry; DiLaura, Robert P; Overcash, Marc; Lehmann, Harold P; Eichmann, David; Athey, Brian D; Scheuermann, Richard H; Anderson, Nick; Starren, Justin; Harris, Paul A; Smith, Jack W; Barbour, Ed; Silverstein, Jonathan C; Krusch, David A; Nagarajan, Rakesh; Becich, Michael J
Clinical and translational research increasingly requires computation. Projects may involve multiple computationally oriented groups including information technology (IT) professionals, computer scientists, and biomedical informaticians. However, many biomedical researchers are not aware of the distinctions among these complementary groups, leading to confusion, delays, and suboptimal results. Although written from the perspective of Clinical and Translational Science Award (CTSA) programs within academic medical centers, this article addresses issues that extend beyond clinical and translational research. The authors describe the complementary but distinct roles of operational IT, research IT, computer science, and biomedical informatics using a clinical data warehouse as a running example. In general, IT professionals focus on technology. The authors distinguish between two types of IT groups within academic medical centers: central or administrative IT (supporting the administrative computing needs of large organizations) and research IT (supporting the computing needs of researchers). Computer scientists focus on general issues of computation such as designing faster computers or more efficient algorithms, rather than specific applications. In contrast, informaticians are concerned with data, information, and knowledge. Biomedical informaticians draw on a variety of tools, including but not limited to computers, to solve information problems in health care and biomedicine. The paper concludes with recommendations regarding administrative structures that can help to maximize the benefit of computation to biomedical research within academic health centers.
PMID: 19550198
ISSN: 1938-808x
CID: 3586362

Exploring the ability of natural language processing to extract data from nursing narratives

Hyun, Sookyung; Johnson, Stephen B; Bakken, Suzanne
Natural Language Processing (NLP) offers an approach for capturing data from narratives and creating structured reports for further computer processing. We explored the ability of a NLP system, Medical Language Extraction and Encoding (MedLEE), on nursing narratives. MedLEE extracted 490 concepts from narrative text in a sample of 553 oncology nursing process notes. The most frequently monitored and recorded signs and symptoms were related to chemotherapy care, such as adverse reactions, shortness of breath, nausea, pain, and bleeding. In terms of nursing interventions, chemotherapy, blood culture, medication, and blood transfusion were commonly recorded in free text. NLP may provide a feasible approach to extract data related to patient safety/quality measures and nursing outcomes by capturing nursing concepts that are not recorded through structured data entry. For better NLP performance in the domain of nursing, additional nursing terms and abbreviations must be added to MedLEE's lexicon.
PMCID:4415266
PMID: 19574746
ISSN: 1538-9774
CID: 3586372

Voice capture of medical residents' clinical information needs during an inpatient rotation

Chase, Herbert S; Kaufman, David R; Johnson, Stephen B; Mendonca, Eneida A
OBJECTIVE:To identify some of the challenges that medical residents face in addressing their information needs in an inpatient setting, by examining how voice capture in natural language of clinical questions fits into workflow, and by characterizing the focus, format, and semantic content and complexity of their questions. DESIGN/METHODS:Internal medicine residents captured information needs on a digital recorder while on a hospital inpatient service and then participated in semi-structured interviews. MEASUREMENTS/METHODS:Interviews were analyzed to identify emergent themes. Recorded questions were analyzed for focus (diagnosis, treatment, or epidemiology) and format, either foreground (specific knowledge relating to an individual patient) or background (general knowledge about a condition). Semantic concepts and types were identified using MetaMap (UMLS - Unified Medical Language System) and manually. RESULTS:Voice recording of questions appeared to unmask residents' latent information needs. Although residents were able to record questions during workflow, there was a delay from the time questions materialized to when they were recorded. Question focus was distributed among diagnosis (32%), treatment (40%), and epidemiology (28%), and the majority of questions were background (69%). Questions were semantically complex; foreground and background questions averaged 12.6 (SD 6.0) and 9.1 (SD 6.0) UMLS concepts, respectively. MetaMap failed to recognize concepts when residents used acronyms or abbreviations or omitted key terms. CONCLUSIONS:We found that it is feasible for residents to capture their clinical questions in natural language during workflow and that recording questions may prompt awareness of previously unrecognized information needs. However, the semantic complexity of typical questions and mapping failures due to residents' use of acronyms and abbreviations present challenges to machine-based extraction of semantic content.
PMCID:2732238
PMID: 19261939
ISSN: 1067-5027
CID: 3586322

Iterative evaluation of the Health Level 7--Logical Observation Identifiers Names and Codes Clinical Document Ontology for representing clinical document names: a case report

Hyun, Sookyung; Shapiro, Jason S; Melton, Genevieve; Schlegel, Cara; Stetson, Peter D; Johnson, Stephen B; Bakken, Suzanne
The authors summarize their experience in iteratively testing the adequacy of three versions of the Health Level Seven (HL7) Logical Observation Identifiers Names and Codes (LOINC) Clinical Document Ontology (CDO) to represent document names at Columbia University Medical Center. The percentage of documents fully represented increased from 23.4% (Version 1) to 98.5% (Version 3). The proportion of unique representations increased from 7.9% (Analysis 1) to 39.4% (Analysis 4); the proportion reflects the level of specificity in the document names as well as the completeness and level of granularity of the CDO. The authors shared the findings of each analysis with the Clinical LOINC committee and participated in the decision-making regarding changes to the CDO on the basis of those analyses and those conducted by the Department of Veterans Affairs. The authors encourage other institutions to actively engage in testing healthcare standards and participating in standards development activities to increase the likelihood that the evolving standards will meet institutional needs.
PMCID:2732231
PMID: 19261945
ISSN: 1067-5027
CID: 3586332