Andrew Ho wrote:
On Fri, 30 Apr 2004, Thomas Beale wrote:Firstly, the model is at http://www.openehr.org/Doc_html/Reference/Information/demographic.htm (this link will probably break in 24 hr due to website changeover..).
...
Telephone1/telephone2 and similar ideas are really not good modelling,
and will almost instantly break, as well as having limited use from the
outset in widely different cultures/environments.
Thomas, Just as an example, how would OpenEHR "model" telephone1 and telephone2?
You will see that the object structure is
PARTY
contacts [0..*]
CONTACT
addresses [0..*]
ADDRESSNow consider what it is you really want record: it is things like:
- business hours contacts, e.g. might be a phone, plus email
- out of business hours, might be another phone, plus a mobile, plus a postal address
- emergency number, anytime
- physical home address
- etc
Each "contact" has some purpose and valid time interval (might be repeating, as in the case of "business hours"); then for each contact, e.g. the second one above, there might be more than one kind of "address" - e..g phone, email, postal and so on.
So you can probably see that recording telephone1 and telephone2 in a flat structure are not going to model any of this very normal reality of contacting people.
I agree: examine it carefully, and consider other similar deficiencies in such models, and the combinatorial effects such approaches can have. But I would also say: a lot of these problems are well known, understood and documented in IT; hopefully people here don't want to go and rediscover it all again the hard way.The reason we and many others have gone to the trouble of doing more
than simple-minded modelling is to get out of the numerous problems that
such modelling brings with it.
There are always design trade-offs. Let's investigate this simple example a bit more so we can better understand the benefits and risks of using simple-minded vs. impractical modelling approaches. :-)
- thomas
