This proposal aims to devise algorithms for ad hoc (non-real-time) query of heterogeneous electronic patient record systems (EPRSs) that store patient data in at least three forms: Conventional relational structure, with an attribute represented by a column in a table, Entity-Attribute-Value (EAV) form, where one or more tables record information that includes entity (Patient, Date/Time of Event, etc.), the name or ID of the Attribute on which information is to be stored, and the value corresponding to that attribute, Free text or quasi-structured textual information, such as discharge summaries, and surgical operation notes. The proposed work will evaluate these algorithms in at least two production systems, ACT/DB and a pilot data warehouse at the West Haven, CT, Veterans Administration Medical Center. The user interface will be Web-based and will be designed for expressive power as well as ease of use by analysts who are non-database professionals. Additional research issues will involve integration of the query system with one or more controlled medical vocabularies, integration of information-retrieval (IR) technology with relational database (RDBMS) technology to provide advanced query functionality, and support of complex temporal queries on the data. Finally, the proposed work will explore architectural issues impacting the efficiency of the query process. In particular, research will be performed on utilization of newer database technologies, such as new indexing methods, as well as parallel database implementations.

National Institute of Health (NIH)
National Library of Medicine (NLM)
Research Project (R01)
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Biomedical Library and Informatics Review Committee (BLR)
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Florance, Valerie
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Yale University
Schools of Medicine
New Haven
United States
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Nadkarni, Prakash M; Darer, Jonathan A (2010) Migrating existing clinical content from ICD-9 to SNOMED. J Am Med Inform Assoc 17:602-7
Nadkarni, Prakash M (2010) Drug safety surveillance using de-identified EMR and claims data: issues and challenges. J Am Med Inform Assoc 17:671-4
Brandt, Cynthia A; Argraves, Stephanie; Money, Roy et al. (2006) Informatics tools to improve clinical research study implementation. Contemp Clin Trials 27:112-22
Nadkarni, P M; Brandt, C A (2006) The Common Data Elements for cancer research: remarks on functions and structure. Methods Inf Med 45:594-601
Nadkarni, P M (2003) The challenges of recording phenotype in a generalizable and computable form. Pharmacogenomics J 3:8-10
Deshpande, Aniruddha M; Brandt, Cynthia; Nadkarni, Prakash M (2003) Temporal query of attribute-value patient data: utilizing the constraints of clinical studies. Int J Med Inform 70:59-77
Fisk, John M; Mutalik, Pradeep; Levin, Forrest W et al. (2003) Integrating query of relational and textual data in clinical databases: a case study. J Am Med Inform Assoc 10:21-38
Nadkarni, P M (2002) An introduction to information retrieval: applications in genomics. Pharmacogenomics J 2:96-102
Brandt, Cynthia A; Morse, Richard; Matthews, Keri et al. (2002) Metadata-driven creation of data marts from an EAV-modeled clinical research database. Int J Med Inform 65:225-41
Nadkarni, Prakash; Sun, Kexin; Wiepert, Mathieu (2002) Designing and implementing special-purpose databases: lessons from the pharmacogenetic network. Pharmacogenomics 3:687-96

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