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 > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.openehr.org/mailman/private/openehr-technical_lists.openehr.org/attachments/20100626/b2b981b8/attachment.html>
