Creation of a Common Data Profile for California Regional Immunization Registries Chris K. Kim, MS Information Systems Manager Statewide Immunization Information Systems Immunization Branch California Department of Health Services March 6, 2007

Agenda CA Statewide Immunization Information System (SIIS) CA Regional Registries NIP Implementation Guide CA HL7 Messaging Profile Conclusions March 6, 2007 CA HL7 Profile

The California State Immunization Information System (SIIS) A collaboration of immunization regional registries that ensures the secure, electronic exchange of immunization records to support the elimination of vaccine preventable diseases. Goals Increase Immunization Rates Eliminate both missed opportunities to immunize and unnecessary duplicate immunizations Share complete immunization records between registries in the system March 6, 2007 CA HL7 Profile

California Immunization Registries 9 Regional registries 2 County registries 6 Web-enabled softwares ~ 3 Million kids under 6 years ~ 29% of kids in Registry (2005) ~ 1% of kids move between registries March 6, 2007 CA HL7 Profile

California Immunization Registries’ Challenges No centralized database for the statewide immunization registry Different registry applications independently managed and operated No data link among registries Large scale of population and spectrum of key stakeholders across the state March 6, 2007 CA HL7 Profile

Solution to Current Challenges Electronic exchange of immunization related data. System that supports the electronic request and response for immunization data from one registry to another. Standard that facilitates the participation of all stakeholders, such as regional and county registries, healthcare providers, and multi-jurisdictional provider organizations There is a need to create a common data profile based upon Health Level 7 messaging standards to exchange immunization data. March 6, 2007 CA HL7 Profile

Health Level Seven (HL7) One of American National Standards Institute (ANSI) accredited Standards Developing Organizations operating in the healthcare arena Develops specifications for health data-interchange standard designed to facilitate the transfer of clinical and administrative data reside on different and disparate computer applications in health care settings. March 6, 2007 CA HL7 Profile

HL7 Implementation Guide Implementation Guide for Immunization Data Transactions using Version 2.3.1 of the HL7 Standard Protocol Center for Disease Control and Prevention (CDC), National Immunization Program (NIP) www.cdc.gov/nip/registry American Immunization Registry Association (AIRA) www.immregistries.org To help familiarize developers of immunization information systems with HL7 immunization message definitions and encoding rules and provide a nationally consistent implementation of those messages. The Centers for Disease Control and Prevention (CDC) National Immunization Program (NIP) publishes an implementation guide for immunization data messaging. The title of the guide is “Implementation Guide for Immunization Data Transactions using version 2.3.1 of the Health Level Seven (HL7) Standard Protocol”. Changes to the guide are coordinated through the Data Exchange Steering Committee of the American Immunization Registry Association (AIRA) and its associated work groups. The members of AIRA are committed to advancing the exchange of immunization data using a common protocol. The purpose of the guide is to help familiarize developers of immunization information systems with HL7 immunization message definitions and encoding rules and provide a nationally consistent implementation of those messages. March 6, 2007 CA HL7 Profile

Differences Between CA Message Profile and the Implementation Guide Message Profile: An unambiguous specification of one or more standard HL7 messages Eliminates ambiguity by declaring static and semantic constraints CA HL7 message profile is an extension to the NIP implementation Guide. (version 2.1, 2002) Does not conflict with the guide More constraints Dynamic and static definition HL7 defines a message profile as “an unambiguous specification of one or more standard HL7 messages that have been analyzed for a particular use case”. It prescribes a set of precise constraints upon one or more standard HL7 messages. A message profile eliminates ambiguity in a HL7 message specification by declaring static and semantic constraints for constituent elements of a message and the expected dynamic behavior of conformant application systems. The CA HL7 message profile is an extension to the NIP Implementation Guide. The profile is based upon version 2.1 of the guide published in September 2002. The profile extends the specifications included in the guide. The profiles do not conflict with the guide; however, they are more constrained than the guide. Messages that conform to the profile are conformant with the guide as well; although the converse may not be true. A message profile has dynamic definition and a static definition. March 6, 2007 CA HL7 Profile

CA HL7 Message Profile Why HL7 Version 2.5? MSH 21 Message Profile Identifier Replacement of Composite (CM) datatype with specific composite datatypes Normative fields and component lengths The use of QRF 10 – Search Confidence Threshold 1. This field contains identification of the message profile to which the message is intended to conform. This will aid in message validation by identifying valid assigning authorities. 2. The composite data types are distinctly defined in version 2.5 which enables a field level definition to be constructed 3. Field and component lengths are normative in version 2.5 which provides greater consistency, and 4. QRF 10 field contains a numeric value used to establish a minimum threshold match. It is used in patient look-up transactions where the searching system employs a numeric algorithm for determining potential matches to patient lookups. The value instructs the responding system to return no records for patients whose “match weight” on the look-up was lower than this value. March 6, 2007 CA HL7 Profile

HL7 2.5 Messaging Standard Message Specification Datatype Segment Group Segment Segment field Data element Datatype Simple: No components Composite: An ordered collection of one or more datatype components Coded Table: Collection of code table items HL7 Defined, user defined, or 3rd party defined An HL7 message specification is an ordered collection of one or more segment groups where each segment group is an ordered collection of one or more segments. A segment may be part of more than one segment group; it can also appear more than once within the same segment group. A segment is an ordered collection of fields. Each segment field is an instance of a data element. A data element may appear as a field in more than one segment or as more than one field within the same segment. Each data element is assigned a data type. A datatype may be simple or composite. A composite datatype is an ordered collection of one or more data type components; a simple datatype has no components. A data type component is an instance of a data element. A data element may appear as a component of more than one composite data type or as more than one component of the same composite data type. Segment fields and datatype components may be associated with a code table. A code table is a collection of code table items. Each code table item is a code system term from some code system. A code system may be HL7 defined, user defined, or defined by a third party. A code system term may be used as a code table item in more than one code table but may appear only once within the same code table. March 6, 2007 CA HL7 Profile

HL7 Message Dynamic Definition Use Case Model Describes the purpose for each message exchange Defines the actors Describes the situations when the exchange of a particular HL7 message profile is required Interaction Model Illustrates the sequence of trigger events and the resulting message flows Acknowledgement Requirements Defines the acknowledgments of required or allowed usage of the specified static definition The dynamic definition describes the supported use cases, interactions, and acknowledgement requirements. Use Case Model The use case portion of the message profile dynamic definition documents the scope and requirements for an HL7 message profile or set of message profiles. The use case model documents the purpose for each message exchange; defines the actors, including the sending and receiving applications; and document the situations in which the exchange of a particular HL7 message profile is required Interaction Model The Interaction Model illustrates the sequence of trigger events and resulting message flows between 2 or more systems. It may be in literal or graphical form. Graphical form should be a UML activity diagram. Acknowledgement Requirements The specific HL7 acknowledgments required and/or allowed for use with the specified static definition of the HL7 message profile is defined. Specifically, the dynamic definition identifies whether accept and application level acknowledgments are allowed or required. For any one static definition there may be one or more dynamic definitions. The dynamic definition defines the conditions under which accept and application level acknowledgments are expected. Allowed conditions include: Always, Never, Only on success, and Only on error. March 6, 2007 CA HL7 Profile

CA Message Profile Use Case Diagram March 6, 2007 CA HL7 Profile

CA Message Profile Interaction Model March 6, 2007 CA HL7 Profile

HL7 Message Static Definition Usage Rules Codes to clearly identify the rules governing the presence of specific elements Cardinality The minimum and maximum number of repetitions for specific elements Vocabulary Specification An organized set of code systems and code system terms The static definition describes usage rules, cardinalities, and code systems. Usage Rules Usage refers to the circumstances under which an element appears in a message instance. Some elements must always be present, others may never be present, and others may only be present in certain circumstances. HL7 has defined a set of codes to clearly identify the rules governing the presence of a particular element. These usage codes expand/clarify the optionality codes defined in the HL7 standard. Cardinality Cardinality identifies the minimum and maximum number of repetitions for a particular element (Segment Group, Segment or Field). Cardinalities are expressed as a minimum-maximum pair of non-negative integers. A conformant application must always send at least the minimum number of repetitions, and may never send more than the maximum number of repetitions. Vocabulary Specification Vocabulary specifications declare an organized set of code systems and code system terms. Code system terms are coded concepts including concept codes, concept names, and concept relationships. Code system terms are collected into value sets declared as code tables associated with segment fields and data type components. The static definition declares the value sets for tables associated with coded message elements. Some of the value sets are HL7 defined, third party defined, or user defined. March 6, 2007 CA HL7 Profile

CA Message Profile Static Definitions The usage and cardinality constraints for the constituent message elements Definition for each message type (VXQ, VXX, VXR, QCK, and ACK) Message, segment, and field level definition The static definition portion of the message profile declares the usage and cardinality constraints for the constituent message elements of the CA HL7 message Profile. There is a static definition for each message type (VXQ, VXX, VXR, QCK, and ACK). Each static definition includes a message level, segment level, and field level definition. The static definition also includes a supported elements definition. The supported elements definition is a field level definition containing supported message elements only. March 6, 2007 CA HL7 Profile

CA SIIS HL7 V2.5 Message Profiling IZ messaging implementation guide HL7 v2.5 Messaging standard Preliminary segment level profile SIIS level conceptual data model Map preliminary profile to regional IZ systems Final segment level profile SIIS level logical data model CA SIIS HL7 message level profiles CA SIIS HL7 vocabulary specification March 6, 2007 CA HL7 Profile

Conclusions CA HL7 Version 2.5 Message Profile Version 1.1 is registered with HL7 (Oct. 2006) www.hl7.org Vocabulary mapping is in progress among registries Necessary but intricate process March 6, 2007 CA HL7 Profile

www.ca-siis.org For More Information Special thanks to Abdul-Malik Shakir, Principal Consultant, Shakir Consulting March 6, 2007 CA HL7 Profile

Thank You Contact : Chris K. Kim, MS Email: ckim1@dhs.ca.gov Phone: 510-620-3778 Certified HL7 2.5 Control Specialist Information System Manager Statewide Immunization Information System Immunization Branch California Department of Health Services March 6, 2007 CA HL7 Profile