Hello everyone I am sending this email to clarify the role of ITEM_STRUCTURE in relation to other structures (such as HISTORY and EVENT) both from the point of view of EHR semantics as well as the computational view.
My "problem" in one line is that i can't understand if ITEM_STRUCTURE are there to ensure that their content is interpreted properly semantically or they really "do what they mean" (i.e. they represent tables, lists, trees that have to be populated as such). A related question is also this one: Is it possible that a C_MULTIPLE_ATTRIBUTE constraint pointing to an ITEM_LIST will have upper_unbounded=True? If yes, then ITEM_LIST would have to be dynamically expanding (and this complicates things a little bit but...that's life)...If no, then the contents of ITEM_LIST can be considered static (yay!) and you only need to know that this is an ITEM_LIST for interpretation purposes (which of course is KEY when you come across an ITEM_TREE) This will help me in two points: a) Clarify the role of ITEM_STRUCTURE and use it properly in archetypes and templates b) Be able to assign widgets properly (and later read data off them) when constructing a GUI. A few more notes are available at the end of this message All the best Athanasios Anastasiou What i understand but would like to verify is that ITEM_STRUCTURE do what they say they do, i.e an ITEM_LIST represents a dynamic list (constrained by some C_MULTIPLE_ATTRIBUTE) and an ITEM_SINGLE represents....just one entry (constrained by some C_SINGLE_ATTRIBUTE). But i am a little bit confused for two reasons: a) by what is meant by HISTORY<T>. HISTORY already implies "A list of events" with the type of the list being (point or interval)EVENT<T> which could imply "A [single item or table] of ITEM_STRUCTURE" OR "A [list,tree] of ITEM_STRUCTURE"....and this is where it gets confusing. Does that mean that all of the following are valid? (with respect to HISTORY<T>) *) a dynamic list of events containing dynamic lists of item structure (the history.events can expand and so can the item structures held by events) *N1) a dynamic list of events containing static lists of item structure (events can expand, but each event is supposed to simply contain a list of items that is actually fixed in size). (dynamic and static expanded for the following lines as well) *) A list of trees *) a list of tables *) a list of single values (this is the most intuitive thing....For example, a time series represented as a history of point events of single_value...) b) by the explanation given in the specs With reference to (*N1) above: The example that is given in the spec for ITEM_LIST is that of "parts of an address". This is what leads me to believe that ITEM_LIST is not supposed to be a dynamic list but just something THAT IS TO BE INTERPRETED AS A LIST but from a computational point of view is just a list. I really do hope this makes sense. (I have gone through section 6 in "data_structures.pdf" and that again points to ITEM_STRUCTURE being used for interpretation rather than "definition" :-/)
