Negation Sources

Back to Negation Requirements

• Werner Ceusters, Peter Elkin and Barry Smith, “Negative Findings in Electronic Health Records and Biomedical Ontologies: A Realist Approach”, International Journal of Medical Informatics 2007; 76: 326-333. PMC2211452.
  • "We introduced a new family of ‘lacks’ relations into the OBO Relation Ontology. . . . By expanding the OBO Relation Ontology, we were able to accommodate nearly all occurrences of negative findings in the sample studied."
• Werner Ceusters, Peter Elkin and Barry Smith “Referent Tracking: The Problem of Negative Findings” (MIE 2006), Studies in Health Technology and Informatics, vol. 124, 741–6. (This issue also published as Ubiquity: Technologies for Better Health in Aging Societies. Proceedings of MIE2006, edited by Arie Hasman, Reinhold Haux, Johan van der Lei, Etienne De Clercq, Francis Roger-France, Amsterdam: IOS Press, 2006.)
  • "Referent tracking" assigns IDs to things to avoid confusion, e.g., when two people assert that a patient has a fracture and it cannot be determied whether they are the same fracture. To the extent that particulars have identifiers, this is in line with Restful (or OWLish) URIs. But they are also required to be unique. Another constraint is the identifiers are only given "real world phenomena," so the question is how to handle something negated. The authors propose a new "lacks" relationship for describing particulars that don't exhibit identified universals.
• Alan Rector, What's in a Code?
  • On separation of ontology from terminology & use of "situation" construct to harmonize positive & negative assertions
• Alan Rector, Negation & Null Values (rough notes)
  • On preference for "absent" to "negation," at least at first
• SNOMED CT Technical Implementation Guide: see 7.8.2.4.7 Retrieving absent findings
  • This section discusses how negation changes the rules for subsumption testing. The solution is to reverse the candidate/predicate relation for Situation with Explicit Context findings using "known absent" or a descendant.
  • Note that this approach assumes a pattern of Procedure with explicit context. The pattern of an Observable with value "absent" is not addressed.
  • This approach can probably be generalized.
  • Note: TiG in revision. This information can be reviewed in a prior version, but it is subject to change and is not a current SI publication.
• Edward Cheatham, SNOMED CT Post-Coordination rules, Draft guidance document. NHS NPFIT, document NPFIT-FNT-TO-DPM-0311.01
  • Guidance suggests storing "close-to-user" forms is a more conservative approach, and that canonical forms can be derived for data operations.
• Gerd Wagner, Web Rules Need Two Kinds of Negation
  • Seems to address case of inferred vs explcit negation, but examples cloud the issue. Suggests that because the richness of domain information does not fit neatly into Boolean categories, Boole needs more values (as opposed to not using a Boolean operator).
• HL7 Version 3 Reference Information Model
  • Observation.valueNegationInd 6.36.2 "This attribute should only be used when the terminology used for Observation.value is not itself capable of expressing negated findings. (E.g. ICD9)."
  • Act.actionNegationInd 6.5.5 "The actionNegationInd works as a negative existence quantifier on the actual, intended or described Act event. In Event mood, it indicates the defined act did not occur. In Intent mood, it indicates the defined act is not intended/desired to occur. In Criterion mood, it indicates that the condition is based on the non-occurrence of the event. It is nonsensical to have a negationInd of true for acts with a mood of definition. The actionNegationInd negates the Act as described by the descriptive properties (including Act.code, Act.effectiveTime, Observation.value, Act.doseQty, etc.) and any of its components."