Clinical LOINC® Tutorial Documents

Clinical LOINC Meeting

Daniel J. Vreeman, PT, DPT, MSc Assistant Research Professor, Indiana University School of Medicine Associate Director of Terminology Services, Regenstrief Institute, Inc

07.15.2010 Copyright © 2010

Overview •  Origins of a Document Ontology •  HL7/LOINC Document Ontology Model •  Evaluation, Evolution, Ongoing

Development – Empiric analyses

•  Future directions

Origins of a Document Ontology

Rationale •  As with other domains, local systems have

idiosyncratic names for clinical documents •  Need a common, controlled vocabulary •  Needed for HL7 CDA standard

–  HL7 v2 too

•  Timeline –  06/2000 Document Ontology Task Force –  09/2003 First axis values and LOINC codes –  ~2005 Expanded SMD domain –  10/2007 Revised axis value approval

Document Type Codes •  Created to provide consistent semantics

for names of documents exchanged b/w independent systems

•  Supported Uses – Retrieval – Organization – Preparation of templates – Display

Frazier P, Rossi-Mori A, Dolin RH, Alschuler L, Huff SM. The creation of an ontology of clinical document names. Stud Health Technol Inform. 2001;84(Pt 1):94-8.

What is a Document? •  Document = Collection of information

–  Sentences, sections –  Distinguished from “panels”, which have

enumerated discrete contents of result elements

•  Formal Document Ontology model/rules apply to “clinical notes” –  Clinical document (per HL7 CDA), produced by

clinicians spontaneously or in response to a request for consultation

–  Does not apply to “reports”, produced in response to an order for a procedure

Approach •  Started with empiric analysis of over 2000

document names – Mayo, 3M/Intermountain, VA in SLC, VA in

Nashville

•  Find the level of granularity that best meets the exchange use case

Finding the Commonality •  Ultra-specific local names:

–  Dr. Evil’s Friday Afternoon Pain Clinic Note

•  Generalizable elements: –  Outpatient Pain Clinic Note

•  Local codes may still be needed –  Can send both local and universal codes in HL7 –  Mapping to the universal code enables

interoperability and aggregation

Document Ontology Model Multi-axial / Poly-hierarchical

Names Based on Document Content

•  Names based on the expected information content

•  NOT based on the document format – Text, scanned images, structured entry form,

XML, etc would all have the same LOINC code if the information content was the same

Assume that these other important attributes would be sent in different fields of the message

What’s NOT in a Document Name

•  Specific author •  Specific location of service or dictation •  Date of service •  Status (e.g. signed, unsigned) •  Security/privacy flags (protected) •  Updates/amendments to a document

Assume that these other important attributes would be sent in different fields of the message

Model of Document Names •  Subject Matter Domain

–  E.g. Cardiology, Pediatric Cardiology, Physical Therapy

•  Role –  Author training/professional classification (not @ subspecialty) –  E.g. Physician, Nursing, Case Manager, Therapist, Patient

•  Setting –  Modest extension of CMS’s definition (not equivalent to location) –  E.g. Inpatient Hospital, Outpatient, Emergency Department

•  Type of Service –  Service or activity provided to/for the patient (or other subject) –  E.g. Consultation, History and Physical, Discharge Summary

•  Kind of Document –  General structure of the document –  E.g. Note, Letter, Consent

Rules for Constructing Names •  LOINC has enumerated value lists for axes

–  Published in Users Guide –  Development edition at loinc.org

•  Names need a Kind of Document value and at least one of the other four axes

•  Combinations from within an axis –  Allowed where they make sense (SMD, Service) –  Represented with a plus (+)

•  LOINC Class = DOC.CLINRPT

Component   Prop   Time   System   Scale   Method  

<Type  of  Service>  <Kind  of  Document>   Find   Pt   <Se8ng>   Doc   <SMD>.<Role>  

Example LOINC Codes Component   Prop   Time   System   Scale   Method  

Group  counseling  note   Find   Pt   InpaBent  Hospital   Doc   {Provider}  

EvaluaBon  and  management  note   Find   Pt   OutpaBent   Doc   {Provider}  

EvaluaBon  and  management  note   Find   Pt   {Se8ng}   Doc   {Provider}  

History  and  physical  note   Find   Pt   {Se8ng}   Doc   {Provider}  

IniBal  evaluaBon  note   Find   Pt   {Se8ng}   Doc   Physician  

Subsequent  evaluaBon  note   Find   Pt   {Se8ng}   Doc   Nurse  PracBBoner  

{curly braces} notation: send that content as a separate item in the message (field or segment)

Hierarchy in LOINC •  Constructed a first-pass Component hierarchy

based on the Type of Service axis –  Ignored Kind of Document

•  Multi-axial hierarchy is generated based on the component hierarchy –  (available as separate download)

•  Could imagine construction of other hierarchies, like context-specific use cases

Hierarchy in LOINC

Evaluation, Evolution, and Development We’re not done yet

Ontology Evolution and Refinement

•  Ongoing evaluation and evolution •  Exceptional contributions from Columbia

University and the VA •  In particular, expanded original SMD value

list with ABMS specialty names and iterative discussion

Shapiro  JS,  Bakken  S,  Hyun  S,  Melton  GB,  Schlegel  C,  Johnson  SB.  Document  ontology:  supporting  narrative  documents  in  electronic  health  records.  AMIA  Annu  Symp  Proc.  2005:684-­‐8.  

Iterative Evaluation Case Study: NYPH-CUMC

SMD   Role   Se8ng   Type  of  Service   Kind  of  Document   Overall   Dis?nct    Original  CDO   26.7%   99.9%   99.9%   43.5%   100%   23.4%    

(n=894)  

7.9%  

Expanded  CDO   98.6%   100%   100%   99.9%   99.9%   98.5%  

(n=935)  

39.1%  

•  Hyun  S,  Shapiro  JS,  Melton  G,  Schlegel  C,  Stetson  PD,  Johnson  SB,  Bakken  S.  Iterative  evaluation  of  the  Health  Level  7-­‐-­‐Logical  Observation  IdentiOiers  Names  and  Codes  Clinical  Document  Ontology  for  representing  clinical  document  names:  a  case  report.  J  Am  Med  Inform  Assoc.  2009  May-­‐Jun;16(3):395-­‐9.  

•  Summary  •  More  documents  could  be  fully  speciOied  in  with  the  expanded  CDO  •  Many  documents  map  to  one  LOINC  code  –  factor  of  local  names  

and  suitable  LOINC  values  •  Inter-­‐rater  reliability  was  very  good  

Nursing SMD   Role   Se8ng   Type  of  Service   Kind  of  Document   Overall   Dis?nct    

SMD-­‐enhanced  CDO  (2005)  

74%   100%   100%   100%   100%   74.5%  

(n=94)  

33%  

•  In  a  separate  analysis,  38%  of  the  section  headings  (n=308)  from  nursing  documents  could  be  mapped  to  existing  LOINC  codes  •  Hyun  S,  Bakken  S.  Toward  the  creation  of  an  ontology  for  nursing  

document  sections:  mapping  section  names  to  the  LOINC  semantic  model.  AMIA  Annu  Symp  Proc.  2006:364-­‐8.  

Hyun  S,  Shapiro  JS,  Melton  G,  Schlegel  C,  Stetson  PD,  Johnson  SB,  Bakken  S.  Iterative  evaluation  of  the  Health  Level  7-­‐-­‐Logical  Observation  IdentiOiers  Names  and  Codes  Clinical  Document  Ontology  for  representing  clinical  document  names:  a  case  report.  J  Am  Med  Inform  Assoc.  2009  May-­‐Jun;16(3):395-­‐9.  

German University Hospital •  Used LOINC v2.24 (original DocOnt terms) •  Of 86 the document types for 1.2 million

documents: –  44% mapped to LOINC –  44% had available mapping deemed not specific

enough –  12% had no LOINC match

•  A LOINC code existed for 93.1% of documents in their set (by volume)

Dugas  M,  Thun  S,  Frankewitsch  T,  Heitmann  KU.  LOINC  codes  for  hospital  information  systems  documents:  a  case  study.  J  Am  Med  Inform  Assoc.  2009  May-­‐Jun;16(3):400-­‐3.  

Ongoing Development

Ongoing Development •  A work-in-progress •  LOINC Users’ Guide is the definitive

source for current policy – Always available at http://loinc.org

•  Collaboration/discussion – Clinical LOINC meetings, HL7 SDTC – LOINC website – LOINC Users’ Forum: http:/forum.loinc.org

Future Directions

Future Directions •  Continued harmonization of v1 and v2

axis values •  Axis definitions •  Extension/refinement to other Kind of

Documents •  Empiric analysis of document contents