Does mapping to SNOMED CT improve precision of subjective clinical evaluations ?

1. Does mapping to SNOMED CT improve precision of subjective clinical evaluations? SHI2010 presentation KirstineRosenbeckGøeg & Anne Randorff Rasmussen

2. Semantic of clinical documentation Introduction

3. Ambiguous documentation “Impairment of vision” Impairment causing change of occupation First diagnose Worsening of something chronic

4. A problem? • Interview 2009 “Vi harnoglebegrebersom vi harbrugtiårevis, eksempelvistilladeligblødning..... nogen der siger, at det er 100ml, mens andre siger at det er det i hvert fald ikke. Så der opdager vi, at vi ikke har den sammeopfattelse. Sådermå vi bliveenigeom at tilladeligblødninger under 100ml, hvismorenellers har det godt, blodtrykket holder og hun ikke besvimer. Der var så meget mere, der skulle knyttes til sådan et begreb....” • Rector 1999 “Common usage may differ from the expectations of information retrieval, e.g. it may seem odd to say that ‘The fingernail is a part of the arm’, but it would be an error not to retrieve ‘evulsion of nail’ under ‘trauma to upper extremity’.” Interview 2009: http://projekter.aau.dk/projekter/files/17651356/speciale-rapportTilUdskrift.pdf Rector 1999: Why is terminology so hard? Method Inform Med 1999; 38: 239–52

5. A problem? • Increasingly possible to • Exchanging information to perform shared care • Use data for statistical purposes • Characterised by • No input validation • Most likely to stay in one organisation and being used only for patient treatment purposes Semantic precision!

6. Mapping subjective evaluations to SNOMED CT Method

7. Method • Two cases • Tolerable bleeding/ Tilladeligblødning • Eating too little/ Småtspisende • Charaterised by • Real life examples of clinical evaluations • From spring 2009 • Expressed difficulties in mapping from paper documentation to electronic documentation • Three approaches to improve precision using SNOMED CT • Mapping to existing pre-coordinated SNOMED CT terms consisting of a finding and a qualifier. Map the evaluation as is, without interpretation. • Mapping by analysing the clinical situation/context in which the evaluation is obtained. • Mapping by nesting the subjective evaluation with the rationale behind the evaluation.

8. SNOMED CT mappings Results

9. Existing pre-coordinated terms

10. Adding the context of the finding Finding: Tolerable bleeding Finding: Eating too little Context: During labour SNOMEDCT mapping Context: Screening, some time duration Maternal blood loos within normal limits Inadequate dietary caloric intake, continual Inadequate dietary caloric intake, continual

11. Nesting observation and evaluation

12. Choosing between mappings Discussion

13. Discussion • A study with only two clinical expressions – pros and cons • Choosing between the three approaches? • Mapping directly is not recommended based on the results of this study • Considering the clinical situation and consequences of different mappings • Asking clinical experts • Can levels of precision be pre-specified?

14. Correspondence: Kirstine Hjære Rosenbeck PhD Fellow, Aalborg University Department of Health Science and Technology E-mail: kirse@hst.aau.dk Phone:+45 9940 8835