Clinical Guidelines

1. Clinical Guidelines Veli Biçer

2. Outline • Evidence-Based Medicine • Clinical Guidelines • Developing Guidelines • Computerized Clinical Guidelines • Arden Syntax • GEM • PROforma & Arezzo

3. Outline cont’d • Asbru & DeGel • GUIDE & NewGuide • MyHeart • EON & Athena • GLIF • Towards Standardization • What is next? • References

4. Evidence-Based Medicine • Advocates the use of up-to-date “best” scientific evidence from healthcare research as the basis of making decisions. It offers: • Objective way to determine high quality and safety standards • The process of transfering clinical findings into practice • Potential to reduce healthcare costs.

5. Clinical Guidelines • “systematically developed statements to assist practitioners and patients on decisions about appropriate health care for specific circumstances" [Field and Lohr [1990] ]

6. Developing Guidelines • Prioritizing Guideline Topic: • Major causes of mortality for a population • Uncertainty about the appropriateness of healthcare • Need to conserve resources in providing care • Cardiovascular Diseases is a major category.

8. Developing Guidelines • The topic is usually refined since the task of developing a guideline for Cardiovascular diseases is considerable • Care Elements: • Primary (The initial and nonspecialized health care) • Secondary (Specialist care in a hospital setting ) • Tertiary (Services provided by highly specialized providers and tech.) • Aspects of Management: • Screening • Diagnosis • Drug Therapy • Risk Factor Management

9. Developing Guidelines • Setting • Inpatient • Outpatient • Time Frame • Emergency • Acute • Chronic

12. Developing Guidelines • Identifying and Assessing the evidence • Best done by systematic review. • The Cochrane Library contains references to over 218000 clinical trials • http://www.cochrane.org/ • Once gathered, the evidence is interpreted and translated into CPG.

15. Computerized Clinical Guidelines • Most clinical guidelines are text-based • All of them is not accessible online • Physicians have difficulties in deciding which of multiple guidelines best pertains to their patient • A clear need for effective guideline-support tools at the point of care • To be effective, these tools: • need to be grounded in the patient's record • must use standard medical vocabularies • should have clear semantics • must facilitate knowledge sharing

16. Computerized Clinical Guidelines • Approaches to Electronic Guideline Representation • Formal Representation Specification • Encoding logic into application-specific format • Guideline Modeling Methodologies: • Rule-based: Arden Syntax • Logic-based : PROforma • Workflow: GUIDE, GLIF

17. Arden Syntax • HL7/ANSI standard • Current approved version is 2.1 • Standard, formal procedural language that represents medical algorithms in clinical information systems as Medical Logic Modules (MLMs). • MLM: an independent unit in a health knowledge base. It contains: • Maintenance Information • Links to other sources • Logic to make a single decision

18. Arden Syntax maintenance: title: Hepatitis B Surface Antigen in Women;; mlmname: hepatitis_B_mlm;; arden: version 2.1;; ... library: keywords: hepatitis B; citations: 1. Goldman L, Cook EF, et al. A computer protocol to predict myocardial infarction. N Engl J Med 1988;318(13);; ... knowledge: data: penicillin_storage := event {store penicillin order} ;; evoke: penicillin_storage;; evoke: 3 days after time of creatinine_storage;…;; var1 := call my_interface_function with param1, param2; logic: if last_creat is not present then alert_text := "No recent creatinine available. Consider ordering creatinine before giving IV contrast."; conclude true; end if;; end:

19. Arden Syntax • Advantages: • Not a full-feature programming language; Suitable for Clinicians. • Provides explicit links to data, trigger events. • Defines how an MLM can be called (evoked) from a trigger event. • Brings particular support for time functions. • HL7/ANSI standard • Used by Commercial DSSs.

20. Arden Syntax • The basic format is not appropriate for developing complete electronic guideline applications • Not as declarative as GLIF • In case of an interaction with a clinical database to provide alerts and reminders, the encoding of clinical knowledge (MLM) may vary due to database schema, clinical vocabulary.

21. GEM • Guideline Elements Model • XML-based guideline markup model • International ASTM (American Society for Testing and Materials) standard. • The free-text is markup in XML.

23. PROforma • A formal knowledge representation language • EU 4th Framework Health Telematics PROMPT project • Guideline is modeled as a set of: • Tasks • Data Items • Tasks are divided into: • Actions • Enquiries • Decisions • Plans • PROforma software consists of a graphical editor to support the authoring process, and an engine to execute the guideline specification. • Two major tools: AREZZO, TALLIS

24. PROforma

25. AREZZO • Software to create and run clinical guidelines based on PROforma • Commercial • Two main components: Composer, Performer • PROforma provides some rules supported by AREZZO • Performer has Microsoft COM Interface

29. Asbru • The Asgaard project led by the Vienna University of Technology and Stanford Medical Informatics, 1998 • A task-specific and intention-based plan representation language • Embody clinical guidelines and protocols as time-oriented skeletal plans • Regarding the timing, the plans can be Sequential, Parallel, Any-order, Unordered.

31. Asbru <plan-library> <library-info title="Skeleton of a Plan Library“/> <library-defs> <domain-defs>…</domain-defs> <variable-def name="List-1" scalar-or-not="list" type="string"> <comment text="List-1 is a list of strings"/> </variable-def> <constant-def name="PI"> <numerical-constant unit="amount" value="3.1415"/> </constant-def> <function-def class-name="asgaard.checkit“ method-name="add_em_up“ name="add“ return-type="length"/> </library-defs> <plans> <plan-group> <plan name="Plan-A">…</plan><plan name="Plan-B">…</plan> </plan-group> </plans> </plan-library>

33. Asbru • Records can also be defined in domain definitions and used as an interface to plans

34. DeGel • Digital Electronic Guideline Library • Developed tools to support the development and implementation of guideline applications. • “Expert physicians cannot program in guideline specific language, while engineers do not understand the clinical semantics” • Problem: “How will the large mass of free text guidelines be converted to a formal machine-readable language?”

35. DeGel • Based on a hybrid (multiple-format) electronic representation of guidelines • A guideline is first converted from free text into semantically semi-structured text • Then from semi-formal language by a medical expert using a markup editor, to a fully formal representation by a knowledge engineer • The current default target language is Asbru

36. DeGel

37. DeGel • The framework provides the following tools: • Uruz - Gradual conversion of free-text clinical guidelines into a machine-comprehensible representation in a given target guideline ontology • IndexiGuide - Manual or automated classification of clinical guidelines along multiple semantic axes • Vaidurya - Search and retrieval of clinical guidelines represented in free text, or in a semi-structured format that uses the labels of a given target ontology • VisiGuide - Visualization and browsing of a set of guidelines in a target ontology

38. Uruz • Guideline markup tool • Similar to GEM Cutter Editor • Source guideline (free-text) is loaded and marked up with semantic labels of the target ontology. • The target ontology can only be Asbru or GEM • The result is an XML document

39. DeGel URUZ

41. Uruz • Plan Body Builder: • Specific to Asbru • Used for defining guidelines control structure • Decompose actions into atomic actions and other sub-guidelines

44. IndexiGuide • Allows medical experts to index the guidelines with semantic axes • Semantic axes can be signs, symptoms, diagnostic findings, disorders, treatments and so on. • Semantic axes are headers of standardized vocabularies such as MeSH, ICD-9, CPT

46. Vaidurya • Guideline search and retrieval tool • The user can search based on semantic axes • The marked-up guidelines can also be queried for the existence of the terms within internal context

48. Visiguide • Visualization of multiple and single guidelines • Free text, semi-structured text and formal language (Asbru). • Organizes the guidelines along semantic axes

50. GUIDE- NewGuide • GUIDE 1998 • Reengineered to NewGuide in 2002 • Laboratory for Medical Informatics, Department of Computer and System Science, University of Pavia, Italy • The Guide environment integrates three main independent modules: • Guideline Management System (GlMS) (providing clinical decision support) • Electronic Patient Record (EPR) • Workflow Management System (WfMS or CfMS) (providing organisational support)