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Interoperability of Data and Knowledge in Healthcare Systems A CAS-747 presentation by: Reza Sherafat [email protected] March 28, 2006 Dept. Computing and Software McMaster University CAS 747: Software Architecture and Reverse Engineering Agenda Current trends in Healthcare Clinical decision support systems Data Interoperability problem Data mining results as the source of knowledge Knowledge interoperability Integration of data mining results with clinical guidelines (plus some case studies) Conclusion References CAS 747: Software Architecture and Reverse Engineering Winter 2006 Current trends in Healthcare The Healthcare professionals are overwhelmed with information. Preventable medical errors cause thousands of deaths each year and loss of billions of dollars. Healthcare information systems are deployed for various purposes, telemedicine, patient care, Electronic Health Records and decision support. A good start by many standards organizations to define and maintain healthcare standards. HL-7 (most popular healthcare data standard) CAS 747: Software Architecture and Reverse Engineering Winter 2006 Clinical decision support systems (CDSS) Effectiveness of clinical decision support systems (a question to be answered) Even a recommendation system should NOT to flood the practitioner with so many [irrelevant] cases and also should NOT ignore possible important cases. Many different approaches to provide decision making support. We focus on guideline-based CDSS that try to support “clinical best practices” at the point of care decision making. Arden Syntax by HL-7 Guideline Interchange Format (GLIF) CAS 747: Software Architecture and Reverse Engineering Winter 2006 Arden Syntax The idea behind Arden Syntax is to have a simple, yet powerful enough procedural language that can encode the necessary logic for deciding upon a single problem. Decision making knowledge is encoded as IF-THEN rules in separate Medical Logic Modules (MLM). Each module is responsible for making a single decision and is run on an engine that can access the EHR systems. Based on the result of evaluation of the rules an action (an alert or reminder) is taken. A library of modules Modules have data sections that should be mapped to institution specific data repositories; the rest of the module is already ready to use. CAS 747: Software Architecture and Reverse Engineering Winter 2006 Arden Syntax (Cont’d) knowledge: type: data_driven;; data: last_creat := read last {"Creatinine level"}; last_BUN := read last {"BUN level"}; ;; evoke: ct_contrast_order;; logic: if last_creat is null and last_BUN is null then alert_text := "No recent serum creatinine available. Consider patient's kidney function before ordering contrast studies."; conclude true; elseif last_creat > 1.5 or last_BUN > 30 then alert_text := "Consider impaired kidney function when ordering contrast studies for this patient." ; conclude true; else conclude false; endif; ;; action: write alert_text || "\nLast creatinine: "||last_creat||" on: "||time of last_creat|| "\nLast BUN: "||last_BUN||" on: "||time of last_BUN ; ;; urgency: 50;; end: CAS 747: Software Architecture and Reverse Engineering Winter 2006 Guideline Interchange Format (GLIF) Three different types are models are mentioned: A guidelines specification standard 1. Guideline Models 2. Data models Flowchart-like diagrams (Guideline Models) 3. Data mining models 3 levels of abstraction [3] : Conceptual modeling Computable level Implementation details CAS 747: Software Architecture and Reverse Engineering Winter 2006 Conceptual Modeling (Level 1) The conceptual models have simple building elements (steps): action step, patient state step, decision step, branch step and synchronization step It is easy to build and understand models Some steps may involve user interaction, access to a data source or triggering an event. CAS 747: Software Architecture and Reverse Engineering Winter 2006 Second and third levels in GLIF Computable level deals with encoding the decision making logic (expressions) Implementation level is concerned with how to map and bind the variable to local (institution specific) medical records. CAS 747: Software Architecture and Reverse Engineering Winter 2006 Data Interoperability The semantics of the communication The semantics convey the actual "meaning" of the message. The semantics is conveyed via a set of symbols contained within the communication. An external "dictionary", thesaurus, or terminology A syntax for communication explains the meaning of the symbols as they occur. The syntax defines the structure and layout of the communication. Common syntax representations include ASN.1, XML, X.12, HL7, IDL, etc. Services to accomplish the communication Examples include the post office, a telephone switchboard, SMTP, FTP, Telnet, RPC, ORB services, etc. A channel to carry the communication Examples of channels include written documents, telephones, network connections, satellite links, etc. Source: [7] CAS 747: Software Architecture and Reverse Engineering Winter 2006 Data Interoperability (Cont’d) Three different types are models are mentioned: THE KEY IDEA: Through standardization 1. Guideline Models 2. Data HL-7 has models built a standard Reference Information 3. Data mining models Model (RIM) RIM is in the form of a large class diagram that model the healthcare domain. Some other XML based standards like Clinical Document Architecture (CDA) use RIM as their main data model. CAS 747: Software Architecture and Reverse Engineering Winter 2006 Data Interoperability (Cont’d) RIM Stakeholder_identifier id : ST identifier_type_cd : ID Service_intent_or_order 0..* filler_order_id : IID has_as_participant filler_txt : TX is_entered_at order_id 0..1 order_placed_dttm : DTM order_quantitytiming_qt : TQ placer_order_id : IID placer_txt : TX is_an_instance_of has_as_target report_results_to_phone : XTN 0..* intent_or_order_cd : ID 0..1 participates_in Active_participation participation_type_cd : ID 0..* 0..* is_assigned_to is_assigned 1 0..1 Stakeholder participates_in addr : XAD 1 phon : XTN collects Stake holder Organization organization_name_type_cd : CNE organization_nm : ST 1 standard_industry_class_cd 0..* Organization takes_on_role_of 0..* has_as_participant 0..* is_collected_by Person birth_dttm : DTM gender_cd : CNE marital_status_cd : CNE is_a_subdivision_of primary_name_representation_cd : CNE 0..1 primary_name_type_cd : CNE has_as_a_subdivision primary_prsnm : PN race_cd : CNE Person 0..* participates_in Collected_specimen_sample body_site_cd : CE collection_end_dttm : DTM collection_start_dttm : DTM collection_volume_amt : CQ handling_cd : ID id : IID method_of_collection_desc : TX specimen_additive_txt : ST specimen_danger_cd : ID specimen_source_cd : CE 0..* is_sourced_from is_source_for 0..1 0..1 is_fulfilled_by Observation_intent_or_order patient_hazard_code reason_for_study_cd relevant_clinical_information_txt reporting_priority_cd specimen_action_cd 0..1 Services has_as_active_participant is_target_of is_target_of 0..1 1 takes_on_role_of Patient 1..* fulfills 0..* delivers 0..1 Service_event has_as_target 0..* service_desc : ST 0..* Tar get_par ticipation is_instantiated_as 0..1 ambulatory_status_cd service_event_desc 0..* birth_order_number has_as_targetparticipation_type_cd : CE specimen_received_dttm : DTM is_delivered_during Healthcare_service_provider is_a_role_ofliving_arrangement_cd 0..1 1 1 is_target_of name : CE specialty_cd : CNE Master_service living_dependency_cd 0..* 0..* is_target_of multiple_birth_ind method_cd : CE has_as_target is_performed_at newborn_baby_ind method_desc : TX has_a_primary_providerorgan_donor_ind service_desc : TX Assessm ent preferred_pharmacy_id target_anatomic_site_cd : CE 0..* universal_service_id : CE is_the_primary_provider_for is_a_role_of is_a_role_of 0..* 0..1 0..1 0..1 has_as_primary_facility Individual_healthcare_practitioner Healthcare_provider_organization Clinical_observation desc : TX abnormal_result_ind : ID practitioner_type_cd : CNE 1..* last_observed_normal_values_dttm : DTM nature_of_abnormal_testing_cd : CE is_primary_facility_for clinically_relevant_begin_dttm : DTM 0..1 clinically_relevant_end_dttm : DTM provides_patient_services_at Master_patient_service_location 0..1 is_target_for 0..* 0 ..* provides_services_on_behalf_of observation_value_txt : NM addr : XAD probability_number : NM 0..1 email_address : XTN references_range_text : ST 0..* id : ID value_units_code : CE is_location_for is_included_in nm : ST phon : XTN is_entry_location_for 1 takes_on_role_of has_as_target 0..* Patient Clinical Observation includes 0..1 CAS 747: Software Architecture and Reverse 1Engineering Winter 2006 Data mining results as the source of knowledge Three different types are models are mentioned: Data mining research has been active in 1. Guideline Models building models that can describe or predict. 2. Data models 3. Data mining models Applications of data mining studies: Likelihood of coincidence of particular diseases Adverse drug usage Diagnosis Patient clustering based on risk factors Verification of known medical knowledge CAS 747: Software Architecture and Reverse Engineering Winter 2006 Knowledge interoperability THE KEY IDEA: Through standards Use standards for knowledge sharing and exchange The mined knowledge should be incorporated into the guideline model to be used for decision making at the decision steps. PMML: data mining knowledge is encoded using the PMML standard. GLIF3: Medical knowledge is encoded in guideline models CAS 747: Software Architecture and Reverse Engineering Winter 2006 Framework for interoperability of mined knowledge CAS 747: Software Architecture and Reverse Engineering Winter 2006 Framework for interoperability of mined knowledge (Cont’d) Three phases: Knowledge preparation Interoperation Mining the patients data To make both data and mined knowledge available at the point of care through use of standard Interpretation Access the knowledge base with the patient data that needs decision making CAS 747: Software Architecture and Reverse Engineering Winter 2006 Integration of data mining results with clinical guidelines Guideline Execution Guideline modeling Knowledge Extraction CAS 747: Software Architecture and Reverse Engineering Winter 2006 Integration of data mining results with clinical guidelines (Cont’d) Knowledge extraction Building data mining models on [usually] large data warehouses Guideline modeling Building guideline models PMML encoding Institution specific data bounding Guideline Execution Execution engine will follow the flow defined in the guideline model Accessing patient data from EMR systems Interact with the healthcare personnel Alert, recommend or remind CAS 747: Software Architecture and Reverse Engineering Winter 2006 Integration of data mining results with clinical guidelines (Cont’d) CAS 747: Software Architecture and Reverse Engineering Winter 2006 Implementation Extending Guideline Interchange Format3 (GLIF3) constructs Guideline Execution Environment (GEE) To support the new functionality needed for the data mining models To execute the guideline models, and access/interpret the data mining models Provision of the mined knowledge as webservices when the knowledge base is not available locally Very helpful for small devices; e.g. handheld computers CAS 747: Software Architecture and Reverse Engineering Winter 2006 Case study A decision tree classifier For melanoma skin cancer diagnosis [6] CAS 747: Software Architecture and Reverse Engineering Winter 2006 Case study (Cont’d) CAS 747: Software Architecture and Reverse Engineering Winter 2006 Guideline Execution Environment The guideline execution environment widget Guideline selection list Different flows within a guideline in execution CAS 747: Software Architecture and Reverse Engineering Winter 2006 Guideline’s Meta Model Data mining decision nodes as an ontology class Data mining decision nodes slots CAS 747: Software Architecture and Reverse Engineering Winter 2006 Guideline modeling Slot widget to specify the new attributes of a data mining decision node CAS 747: Software Architecture and Reverse Engineering Winter 2006 Conclusion We described: A knowledge management framework to for data mining results; The environment in which the framework can be deployed; How to integrate data mining results in clinical guidelines; How knowledge interoperability is achieved. CAS 747: Software Architecture and Reverse Engineering Winter 2006 References Incorporating Data Mining Applications into Clinical Guidelines, R. 1. Sherafat, K. Sartipi, The 19th IEEE International Symposium on ComputerBased Medical Systems, 2006 2. Data and Knowledge Interoperability in Distributed Healthcare Systems, R. Sherafat, K. Sartipi, The 13th Annual International Workshop on Software Technology and Engineering Practice, 2005 3. Guideline Interchange Format 3 (GLIF3), www.glif.org 4. Health Level-7 (HL-7), www.hl7.org 5. Arden Syntax, http://hl7.org/library/standards_non1.htm#Arden%20Syntax 6. Data Management Group (DMG), www.dmg.org 7. Rules for melanoma skin cancer diagnosis, http://www.phys.uni.torun.pl/publications/kmk/ 8. Version 3 Intermediate Tutorial - Working the HL7 Version 3 Methodology, George W. Beeler, http://hl7.org/library/datamodel/V3_Tutorials/V3_Intermediate_May00.ppt CAS 747: Software Architecture and Reverse Engineering Winter 2006 Questions ? CAS 747: Software Architecture and Reverse Engineering Winter 2006