Hi Leo, No it works the other way round. All of the null flavours are automatically available unless you specifically constrain them out.
Ian Dr Ian McNicoll office / fax +44(0)141 560 4657 mobile +44 (0)775 209 7859 skype ianmcnicoll ian.mcnicoll at oceaninformatics.com ian at mcmi.co.uk Clinical Analyst Ocean Informatics openEHR Archetype Editorial Group Member BCS Primary Health Care SG Group www.phcsg.org / BCS Health Scotland On 29 June 2010 15:29, Leonardo Moretti <lmoretti at noemalife.com> wrote: > > In the case of "Comment" in openEHR-EHR-OBSERVATION.blood_pressure.v1, the > ADL definition is: > > ELEMENT[at0033] occurrences matches {0..1} matches { -- Comment > value matches { > DV_TEXT matches {*} > } > } > > This means that here I cannot specify a null_flavour for Comment element! > Maybe should this archetype be extended as in the following? > > ELEMENT[at0033] occurrences matches {0..1} matches { -- Comment > value existence matches {0..1} matches { > DV_TEXT matches {*} > } > null_flavour existence matches {0..1} matches { > DV_CODED_TEXT matches { > defining_code matches { > [openehr:: > 271, > 272, > 273] > } > } > } > } > > > Regards > leo > > > Leonardo Moretti wrote: > > > > Ok, Ian, > > using a null value, a null flafour is needed.. For your example cases: > > a) The doctor simply did not add any comment. > > b) The doctor purposefully 'added an empty string' by clicking through > the > > data entry widget, perhaps to signify 'no comment'. > > c) The doctor couldn't add a comment for some other technical / > > environmental reason. > > > > and looking at codes in section 2.3.7 of > > http://www.openehr.org/releases/1.0.2/architecture/terminology.pdf, I > > would use: > > for a) and b): HL7_NullFlavor::10614 (AskedButUnknown), but it doens't > > have an analogous values on opeEHR code system > > c) HL7_NullFlavor::10614 (temporarily unavailable), but also in this case > > it doens't have an analogous values on opeEHR code system > > > > > > Maybe my perplexity is due to an incomplete value set for Null Flavours > > vocabulary found in openEHR specs.. > > > > Should this vocabulary be extended!? > > > > Regards > > leo > > > > > > > > Ian McNicoll-3 wrote: > >> > >> Hi Leo, > >> > >> In pure semantic terms I appreciate the difference but this is > >> practically > >> of no value. > >> > >> What does this empty string mean? > >> > >> Is it? > >> > >> a) The doctor simply did not add any comment. > >> b) The doctor purposefully 'added an empty string' by clicking through > >> the > >> data entry widget, perhaps to signify 'no comment'. > >> c) The doctor couldn't add a comment for some other technical / > >> environmental reason. > >> > >> These are very subtle differences to most clinical staff and I would not > >> want to base any safe querying on assumptions that clinicians would > >> record > >> these differences reliably. > >> > >> If there is a need to positively identify 'no comment', I would model > >> that > >> explicitly but this is rare in clinical practice, and usually is > recorded > >> for medico-legal reasons rather than future querying e.g. 'No known > >> allergies' is a legitimate clinical comment but cannot ever be safely > >> queried upon, since the next clinical statement in the record might well > >> be > >> 'Diagnosis = Penicillin Allergy'. > >> > >> The most significant principle is that we do not normally record 'empty > >> data' at all in openEHR. The data simply does not exist in the clinical > >> record. If some sort of comment is mandatory then using the null is the > >> means to allow an empty comment. > >> > >> I have copied ot the clinical list, as it would be interesting to get > >> some > >> other feedback. > >> Ian > >> > >> Dr Ian McNicoll > >> office / fax +44(0)141 560 4657 > >> mobile +44 (0)775 209 7859 > >> skype ianmcnicoll > >> ian.mcnicoll at oceaninformatics.com > >> ian at mcmi.co.uk > >> > >> Clinical Analyst Ocean Informatics openEHR Archetype Editorial Group > >> Member BCS Primary Health Care SG Group www.phcsg.org / BCS Health > >> Scotland > >> > >> > >> > >> On 29 June 2010 12:26, Leonardo Moretti <lmoretti at noemalife.com> wrote: > >> > >>> > >>> Hi Ian, > >>> in my opinion an empty string has a semantic difference with a null > >>> value. > >>> Empty string is however a valid value. For example, I could have > >>> different > >>> cases for "Comment" in openEHR-EHR-OBSERVATION.blood_pressure.v1: > >>> - a non-empty string with the comment on blood pressure measurement. > >>> - an empty string, meaning that no comment has been given from the > >>> doctor, > >>> because not needed (doctor judges that no comment is necessary) > >>> - a null value, meaning that no comment has been asked to the doctor, > >>> because exluded from the template/GUI. > >>> Or there are an other way to model these three cases? > >>> > >>> Regards, > >>> leo > >>> > >>> > >>> > >>> Ian McNicoll-3 wrote: > >>> > > >>> > Hi Leo, > >>> > > >>> > An important principle under-pinning openEHR is that 'empty' data is > >>> not > >>> > normally recorded, which is consistent with general clinical practice > >>> > information recording. > >>> > > >>> > On this basis, I am not sure I can see the use case for recording "" > >>> i.e. > >>> > Empty text. If a text data entry field is left blank, this would > >>> simply > >>> > not > >>> > be recorded in openEHR data. If the field is mandatory, either the > >>> user > >>> is > >>> > forced to make some sort of entry or perhaps is allowed to select one > >>> of > >>> > the > >>> > null values as you suggest. > >>> > > >>> > Regards, > >>> > > >>> > Ian > >>> > > >>> > Dr Ian McNicoll > >>> > office / fax +44(0)141 560 4657 > >>> > mobile +44 (0)775 209 7859 > >>> > skype ianmcnicoll > >>> > ian.mcnicoll at oceaninformatics.com > >>> > ian at mcmi.co.uk > >>> > > >>> > Clinical Analyst Ocean Informatics openEHR Archetype Editorial Group > >>> > Member BCS Primary Health Care SG Group www.phcsg.org / BCS Health > >>> > Scotland > >>> > > >>> > > >>> > > >>> > On 25 June 2010 16:07, Moretti Leonardo <lmoretti at noemalife.com> > >>> wrote: > >>> > > >>> >> In > >>> >> > >>> > http://www.openehr.org/releases/1.0.2/architecture/rm/data_types_im.pdf > >>> , > >>> >> DV_TEXT is defined as a text item. Among "Invariants" (page 29), I > >>> found > >>> >> that this data type is valid if it is not empty (Value_valid: value > >>> /= > >>> >> void and then not value.is_empty and then not(value.has(CR) or > >>> >> value.has(LF))). > >>> >> > >>> >> Does this mean empty string is not a valid value for DV_TEXT? If so, > >>> why > >>> >> empty string cannot be a valid value? An empty string could be > >>> >> meaningful, with a different semantic than null value! Many textual > >>> >> information could be an empty string (comments, descritpions..). An > >>> >> empty string means that the value is exactly a void string, a null > >>> value > >>> >> means that the information is unknown, not taken, not asked! > >>> >> > >>> >> Regards > >>> >> leo > >>> >> > >>> >> _______________________________________________ > >>> >> openEHR-technical mailing list > >>> >> openEHR-technical at openehr.org > >>> >> http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-technical > >>> >> > >>> > > >>> > _______________________________________________ > >>> > openEHR-technical mailing list > >>> > openEHR-technical at openehr.org > >>> > http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-technical > >>> > > >>> > > >>> > >>> -- > >>> View this message in context: > >>> > http://old.nabble.com/Empty-string-for-DV_TEXT-tp28993527p29022604.html > >>> Sent from the openehr-technical mailing list archive at Nabble.com. > >>> > >>> _______________________________________________ > >>> openEHR-technical mailing list > >>> openEHR-technical at openehr.org > >>> http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-technical > >>> > >> > >> _______________________________________________ > >> openEHR-technical mailing list > >> openEHR-technical at openehr.org > >> http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-technical > >> > >> > > > > > > -- > View this message in context: > http://old.nabble.com/Empty-string-for-DV_TEXT-tp28993527p29024312.html > Sent from the openehr-technical mailing list archive at Nabble.com. > > _______________________________________________ > openEHR-technical mailing list > openEHR-technical at openehr.org > http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-technical > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.openehr.org/mailman/private/openehr-technical_lists.openehr.org/attachments/20100629/710477c2/attachment.html>