Introduction to HL7 Standards: v 2'x

1
Introduction to HL7 Standards v 2.x

• W. Ed Hammond
• February 25, 2008

2
Why use data interchange standards?

• Use of standards is becoming more universal. HL7
  standards are likely to be in use already
• EHRVA and the vendor community support and use
  HL7 standards
• As new items are collected, the HL7 standard is
  easier to accommodate
• Maintenance is not a cost or a problem
• Less work required for new organizations to join
  project
• The work is already done

3
Choices for data interchange

• HL7 v2.n series
• HL7 v3 standard
• Model-based
• HL7 Clinical Data Architecture
• Continuity of Care Document
• Common Document Types

4
Which choice?

• Version 2.x is my immediate recommendation
• Messages are straight forward and the OBX segment
  can carry any data content
• Version 2.x is easy and straight forward to
  implement
• An Implementation Manual with conformance
  agreement for common data elements and the use of
  a common terminology will provide controlled
  interoperability
• Version 2.6 is the latest release

5
version 2.x messaging standard

• Based on an implicit information model
• Focused initially on needs of HIS, later versions
  expanded horizontally into other areas including
  ambulatory care
• Most widely used HL7 standard (gt90 provider
  organizations)
• Events not tightly coupled to profiles
• Makes no formal attempt to define process
• Available with delimiter syntax or with XML
  syntax
• Most currently implemented version is v2.3
• Messages initiated by trigger events

6
v2.x messaging standard (2)

• Uses segments whose contents are positionally
  defined segments are made up of data fields
  which are made up of data elements
• Fields may be repeating
• Much data sent as name-value pairs
• Accommodates any HL7 registered terminology
  expressed as code, name, terminology ID triplet

7
v2.x messaging standard (3)

• Is easy to use and understand quick
  implementation
• Works well within a single enterprise where both
  sender and receiver are tightly bound does not
  work well when sender and receiver are not
  connected
• Has saved money on cost of interfaces
• Will continued to be supported by HL7 in the
  future and will continue to be implemented by
  users

8
v2.x Functional areas

• ADT, Registration, Orders, Results, patient
  financial, query language, immunization
  reporting, clinical trials, adverse drug
  reactions, scheduling, referrals, medical
  records, patient care, problem lists and goals,
  waveforms, personnel management, clinical lab
  automation transactions, master files

9
Version 2.6 chapters

• Introduction
• Control
• Patient Administration
• Order Entry
• Queries
• Financial Management
• Observation Reporting
• Master Files
• Medical Records/ Information Management
• Scheduling
• Patient Referral

• 12. Patient Care
• 13. Clinical Laboratory Automation
• 14. Application Management
• 15. Personnel Management
• 16. Non-US Claims
• 17. Materials Management

AppendixA. Data Definition TablesB. Lower
Layer ProtocolC. BNF DefinitionsD. Glossary
10
The HL7 basic Transaction Model

Lab system Receive A01, send ACK
trigger event
(external) admit event
send HL7 A01 msg receive HL7 ACK msg Adt system
network
11
HL7 Message Message Header - MSH
Addressing the envelope
MSHSMSOR2TMRSICU200802151535passwordAD
TA03MSG1632P2.6ltcrgt
12
HL7 Message - PID Segment
Identify the patient
13
HL7 Message PV1 Segment
Define the visit or encounter
PV111N22002200OR020846WELBYMARCUSGSU
Rltcrgt
14
HL7 Message OBR Segment
Defines information specific to an order
OBR1330769.0001.001DMCRES0000514215RADIS1770
61U/S PEVLICL 199607121145049190
9U999MFIBROIDS, R/O207484CARROLL BA
RBARAA089657BROWNJOANNEltCRgt
15
HL7 Result Message (ORU)
MSH\19981105131523ORUR01ltcrgt PID100
9287829M11SmithJohnJltcrgt OBRZ0063-0LNlt
crgt OBXXCNZ0063-0LN2093467SmitsJltcrgt OBX
Z0092-0LN203BE0004YX12PTXltcrgt
Segment
Data Field
16
OBX the flexible segment
Other data fields include date of observation,
identity of provider giving observation, normal
ranges, abnormal flags
A code that
identifies the data in OBX-5(Temp Reading)
OBXNM11289-6LN38CISOF
17
OBX with a coded value
OBXCE883-9Blood GroupLNF-D1250Group OSM
18
v2.x Syntax
MSH\REGADTMCMIFENG199112311501ADTA04A
DT_A01000001P2.4 EVNA04199901101500199901
10140001199901101410 PID191919GENHOSMR37
1-66-9256USSSASS 253763MASSIEJAMESA19560
129M171 ZOBERLEINISHPEMINGMI49849"" (9
00)485-5344(900)485-5344SHL70002CHL700061
0199925GENHOSAN 371-66-9256 NK11MASSIEEL
LENSPOUSEHL70063171 ZOBERLEINISHPEMINGMI49
849"" [phone](900)545-1234(900)545-1200
EC1FIRST EMERGENCY CONTACTHL70131 NK12MASSIE
MARYLOUMOTHERHL70063300 ZOBERLEINISHPEMINGM
I49849"" [phone](900)545-1234(900)545-
1200EC2SECOND EMERGENCY CONTACTHL70131 NK13 NK
14123 INDUSTRY WAYISHPEMINGMI49849""(9
00)545-1200 EMEMPLOYERHL7013119940605PROGRAM
MERACME SOFTWARE COMPANY PV1OO/R0148ADD
ISON,JAMES0148ADDISON,JAMESAMB 0148ADD
ISON,JAMESS1400AGENHOS1
99501101410 PV2199901101400
199901101400 ROLADCPHL704430148A
DDISON,JAMES OBXNM3141-9BODY
WEIGHTLN62kgF OBXNM3137-7HEIGHTLN1
90cmF DG11190815BIOPSYACODE00 GT11
MASSIEJAMES""""""""171
ZOBERLEINISHPEMINGMI49849"" [phone](
900)485-5344SESELFHL70063371-66-925MOOS
ES AUTO CLINIC 171 ZOBERLEINISHPEMINGMI49849
""[phone] IN100HL70072BC1BLUE
CROSS171 ZOBERLEINISHPEMINGM149849"" (900)
485-53449050 OK