Not that it's dispositive of any larger issue, but doesn't VAS actually record a physical quantity (specifically, the centimeter position on the horizontal line where the patient indicates the level of pain)?
On Tue, February 10, 2009 12:19 pm, Thomas Beale wrote: > <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> > <html> > <head> > <meta content="text/html;charset=ISO-8859-1" > http-equiv="Content-Type"> > </head> > <body bgcolor="#ffffff" text="#000000"> > <a class="moz-txt-link-abbreviated" > href="mailto:Williamtfgoossen at cs.com">Williamtfgoossen at cs.com</a> > wrote: > <blockquote cite="mid:d08.4cff1767.36c30534 at cs.com" type="cite"><font > face="arial,helvetica"><font ptsize="10" family="SANSSERIF" > face="Arial" lang="0" size="2"><br> > <br> > Thomas,<br> > <br> > Thank you for your reply, however it does not satisfy the request. > <br> > <br> > I think that the pain score is indeed not a physical measurable > instrument. <br> > But it is not an Ordinal, in statistical terms it is an Interval if > the > numeric score is used (0, 1, 2, 3 etc up to 10) and a ratio when the > VAS scale is used. <br> > Hence reliability studies have determined that it is useful in > practice. <br> > </font></font></blockquote> > <br> > I certainly didn't mean to imply that things like the pain score were > not useful!<br> > <br> > <blockquote cite="mid:d08.4cff1767.36c30534 at cs.com" type="cite"><font > face="arial,helvetica"><font ptsize="10" family="SANSSERIF" > face="Arial" lang="0" size="2"><br> > However, I would like to have the following<br> > <br> > DV_PhysicalQuantity meeting the PQ requirements from ISO 21090<br> > and the<br> > DV_CodedOrdinal, or DV_Ordinal meeting the requirements for the CO > (Coded Ordinal) from ISO 21090. <br> > The CO does allow the order as we need, and allows the mathematical > operations such as summations, calculations like BMI style, among > others. <br> > <br> > </font></font></blockquote> > <br> > As far as I can see, the current openEHR data types satisfy your needs > (with one exception - see below):<br> > <ul> > <li>DvQuantity - handles all PQ, including with no units</li> > <li>DvOrdinal - handles all ordinals, with any kind of symbols, > including from coding systems</li> > </ul> > I don't understand the need for summations etc for ordinals, because > the general nature of ordinal values is that that symbolically > identify > arbitrary ranges in a value space (e.g. amount of pain, amount of > protein in urine etc). Mathematically they don't satisfy the > requirements to be summable. Can you explain further the intended > semantics here?<br> > <br> > The exception is that neither of the above types handles a > non-integral > 'ordinal' idea. Hence my proposal of DV_SCORE. There are probably > better solutions, I have not thought much about it. I do think > however, > that any solution needs to be mathematically sound, because downstream > data computing relies on that.<br> > <br> > Would you agree with my understanding of the problem as stated > here?<br> > <br> > - thomas<br> > <br> > </body> > </html> > > _______________________________________________ > openEHR-technical mailing list > openEHR-technical at openehr.org > http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-technical >
