One-Way and Round-Trip Analysis Demonstrates Surprising Limitations of Standards-Based Terminology Maps.

The informatics community has a long-standing vision of freely flowing and highly re-usable patient-specific clinical data that improves care quality and safety. We sought to evaluate the extent to which a standards-based mapping approach is sufficient to support semantic interoperability. We simulated large-scale clinical data transmission and measured semantic success between VA and DoD systems via one-way testing (OWT) and round-trip testing (RTT). Simulations were accomplished via SQL queries and production standards-based maps for medications, allergens, document titles, vitals and payers. Success rates for mapping local codes to national standards varied from 62.5% for DoD document titles and medications, to 100% for VA and DoD vital signs. Successful, one-way testing was considerably lower, ranging from 8.52% to 62.7%. Round-trip success rates were lower still, ranging from 1.7% to 76.3%. We present an error framework, lessons learned, and proposed mitigating steps to enhance standards-based semantic interoperability.

Evaluating the implementation of RxNorm in ambulatory electronic prescriptions.

OBJECTIVE: RxNorm is a standardized drug nomenclature maintained by the National Library of Medicine that has been recommended as an alternative to the National Drug Code (NDC) terminology for use in electronic prescribing. The objective of this study was to evaluate the implementation of RxNorm in ambulatory care electronic prescriptions (e-prescriptions). METHODS: We analyzed a random sample of 49 997 e-prescriptions that were received by 7391 locations of a national retail pharmacy chain during a single day in April 2014. The e-prescriptions in the sample were generated by 37 801 ambulatory care prescribers using 519 different e-prescribing software applications. RESULTS: We found that 97.9% of e-prescriptions in the study sample could be accurately represented by an RxNorm identifier. However, RxNorm identifiers were actually used as drug identifiers in only 16 433 (33.0%) e-prescriptions. Another 431 (2.5%) e-prescriptions that used RxNorm identifiers had a discrepancy in the corresponding Drug Database Code qualifier field or did not have a qualifier (Term Type) at all. In 10 e-prescriptions (0.06%), the free-text drug description and the RxNorm concept unique identifier pointed to completely different drug concepts, and in 7 e-prescriptions (0.04%), the NDC and RxNorm drug identifiers pointed to completely different drug concepts. DISCUSSION: The National Library of Medicine continues to enhance the RxNorm terminology and expand its scope. This study illustrates the need for technology vendors to improve their implementation of RxNorm; doing so will accelerate the adoption of RxNorm as the preferred alternative to using the NDC terminology in e-prescribing.

Building a standards-based and collaborative e-prescribing tool: MyRxPad.

MyRxPad (rxp.nlm.nih.gov) is a prototype application intended to enable a practitioner-patient collaborative approach towards e-prescribing: patients play an active role by maintaining up-to-date and accurate medication lists. Prescribers make well-informed and safe prescribing decisions based on personal medication records contributed by patients. MyRxPad is thus the vehicle for collaborations with patients using MyMedicationList (MML). Integration with personal medication records in the context of e-prescribing is thus enabled. We present our experience in applying RxNorm in an e-prescribing setting: using standard names and codes to capture prescribed medication as well as extracting information from RxNorm to support medication-related clinical decision.

Normalized names for clinical drugs: RxNorm at 6 years.

OBJECTIVE: In the 6 years since the National Library of Medicine began monthly releases of RxNorm, RxNorm has become a central resource for communicating about clinical drugs and supporting interoperation between drug vocabularies. MATERIALS AND METHODS: Built on the idea of a normalized name for a medication at a given level of abstraction, RxNorm provides a set of names and relationships based on 11 different external source vocabularies. The standard model enables decision support to take place for a variety of uses at the appropriate level of abstraction. With the incorporation of National Drug File Reference Terminology (NDF-RT) from the Veterans Administration, even more sophisticated decision support has become possible. DISCUSSION: While related products such as RxTerms, RxNav, MyMedicationList, and MyRxPad have been recognized as helpful for various uses, tasks such as identifying exactly what is and is not on the market remain a challenge.

Aligning tissue banking data models for caBIG interoperability.

MD Anderson Cancer Center strives to share data from its central tissue bank with other institutions via the caBIG data sharing framework. To conform to "NCI Best Practices for Biospecimen Resources", a caGRID compatible model (i.e. caTissue Core/Suite) must be adopted or an existing tissue banking application (TissueStation) must be adapted for interoperability. We present a data model assessment and method used in development of an enterprise strategy for ensuring inter-institution data sharing capabilities.

Exchange of computable patient data between the Department of Veterans Affairs (VA) and the Department of Defense (DoD): terminology mediation strategy.

Complete patient health information that is available where and when it is needed is essential to providers and patients and improves healthcare quality and patient safety. VA and DoD have built on their previous experience in patient data exchange to establish data standards and terminology services to enable real-time bi-directional computable (i.e., encoded) data exchange and achieve semantic interoperability in compliance with recommended national standards and the eGov initiative. The project uses RxNorm, UMLS, and SNOMED CT terminology standards to mediate codified pharmacy and allergy data with greater than 92 and 60 percent success rates respectively. Implementation of the project has been well received by users and is being expanded to multiple joint care sites. Stable and mature standards, mediation strategies, and a close relationship between healthcare institutions and Standards Development Organizations are recommended to achieve and maintain semantic interoperability in a clinical setting.

Use of RxNorm to exchange codified drug allergy information between Department of Veterans Affairs (VA) and Department of Defense (DoD).

Under a congressional mandate, VA and DoD have built a framework to exchange standardized, codified patient drug allergy information through a mediation terminology. Initially, the Unified Medical Language System (UMLS) was deemed to be the most appropriate translator. After both agency files were mapped to UMLS, DoD could understand 45 percent of VA's mapped terms and VA could understand 26 percent of DoD's mapped terms. A significant portion of the non-mediated information was brand names in DoD with generic counterparts in VA. Recently, a Consolidated Health Informatics (CHI) group designated RxNorm as the standard for trade name allergies. An analysis was conducted to estimate mediation improvement using RxNorm. Both agency files were re-mapped to RxNorm. By utilizing the RxNorm defined relationships between brand names and generics and between variants of therapeutic moieties , DoD will understand 74 percent of VA terms and VA will understand 58 percent of DoD terms.

Unicode, UTF-8, ASCII, and SNOMED CT.

SNOMED CT text files are encoded using UTF-8 to allow worldwide distribution and use of the terminology. Incorporating such UTF-8 encoded text into a system not currently using UTF-8 is simplified when the specific range of characters in the imported data is known. This poster describes the superset of ASCII found in the SNOMED CT US/UK Edition January 2003 release.