【高血压英文课件】QualityAssurance-of-the-Content-of

Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,Click to edit Master title style,*,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,Quality Assurance of the Content of a Large DL-based Terminology using Mixed Lexical and Semantic Criteria:Experience with SNOMED CT,Alan Rector,Luigi Iannone,Robert Stevensrectorcs.manchester.ac.uk,2,“A report from the trenches”,SNOMED-CT-mandated terminology for electronic patient records in UK,US,&worldwide aspirations,The result of a merger of two other systems,SNOMED and Clinical Terms v3,Long history with much opportunity for error,Expressed in a Description Logic and now available in OWL,subset of EL+without disjoint axioms,Has been resistant to independent analysis although many known problems,Despite several global QA attempts based on lexical criteria that have identified errors without explaining them,3,Its very big-and classification matters,400,000 Concepts/Classes;1,000,000 axioms,Much of richness only evident in classified form,Most errors only present in classified form,stated,Classified,4,and some classification horrendously complicated(,Skin of Ankle,),5,An experiment of opportunity,The opportunities,Tried to use SNOMED for Commercial Collaboration on Clinical Systems,Tried to use SNOMED as contribution to WHOs revsion of International Classification of Diseases(ICD-11),Problems with both,Therefore,experiment if QA&repair were possible,Conventional wisdom said that it was not,However,we had new resources,Core Problem List Subset from NLM(8500 most used classes),Software to extract“modules”,SNOROCKET Classifier for EL+,4-8GB machines,6,Step 1:Cut it down&find a classifier,Find a subset,UMLS Core Problem List subset-,8500 most used disease concepts,Collected by US National Library of Medicine by combining sets from 6 major institutions.,Extract a“Module”(built into OWL API v3),Use core subset as“signature”,Guaranteed that all inferences,amongst the classes in“signature”,in whole will hold in module,35,000 concepts-including most of anatomy,Find a classifier that can cope-at least two for checking,SNOROCKET(EL+)polynomial time subset of OWL(30 sec),Pellet 2.1(200 sec),FaCT+(250 sec),7,Step 2:Pick some areas of interest to clinicians:some with anomalies already spotted,Myocardial Infarction(Heart attack),Should be a kind of,Ischemic Heart Disease,but wasnt,Hypertension(High blood pressure),Odd to find it a kind of,Soft Tissue disorder,Diabetes,Odd to find it as a,Disorder of the Abdomen,Allergies,Odd to find some but not all autoimmune disorders classified as Allergies.,8,Look up hierarchy(with OWLViz),Let clinicians find important concepts and check them,Face validity and then look up the hierarchy,Check any anomalies against the complete SNOMED in standard browser,Guard against artifacts in various transformations,Trace anomalies to their root,Decide which links to add or break,Decide how to break them,Edit,classify and check,Hierarchies,Usages,Look at classification:,Most initial errors spotted looking upwards,9,OwlViz Upwards for Hypertension,10,And check for the desired result,11,Check in standard browser in full SNOMED(snob.eggbird.eu/),12,Examine definition&formulate solution,Disorder of blood vessel,that,(,Finding site,some,Systemic arterial structure,),and (,Has definitional manifestation,some,Increased blood pressure),),Disorder of blood vessel,that,(,Finding site,some,Cardiovascular system structure,)and (,Has definitional manifestatio,n,some,Increased blood pressure),13,Then check usages for unwanted results-,anything that should relate to arteries instead of Cardiovascular system?,Also look down hierarchy:Combine lexical&semantic search,Hard to spot what is missing,Hypertensive disorders,included some complications as well as kinds of,hypertension,.Did it contain them all?,Use OPPL combining lexical,owl semantics&queries,?C,:CLASS=MATCH(,“.*,Hhypertensive,.*”,),lexical,SELECT,?C,SubClassOf,Thing,open world OWL semantics,WHERE FAIL,?C,SubClassOf,“Hypertensive disorder”,closed world query,BEGIN ADD,?C,SubClassOf,Candidate_hypertensive,END,;,action,Classify and look at odd cases,14,Classify and look at odd cases,15,Look for regularities,Of hypertensive complications,1 linked to,Hypertensive disorder,by property,due to,1 linked to,Hypertensive disorde,r,by property,associated with,2 are subclasses of,Hypertensive disorder,2 not linked at all,No class for,Hypertensive complication,Although there is a class for,Diabetic complication,Regularise,Create classes for,Hypertension,Hypertensive complication,and,Hypertension AND/OR Hypertensive complication,Edit all complications to schema:,Disorder,due,t,o,some,Hypertension,16,Which concept should carry the old ID?,Look at usages of,Hypertensive disorder,All fit,Hypertension,;,none fit,Hypertensive complication,Therefore,label original ID for,Hypertensive disorder,as,Hypertension,New Hierarchy:,Hypertension AND/OR