Hi to all,
While revising my MST archetypes, I came across some confusion on the
use of cardinality and occurences. And when I reread ADL 1.4 and ADL2,
inspected the sample archetypes and then created new ones with Archetype
Editor and also tested with the Workbench my confusion got even more
increased. Here is the problem description and some questions:
As stated in ADL 1.4: "Cardinalities indicate limits on the number of
members of instances of container types such as lists and sets". From a
simpler point of view, what I understand it tells the min and max
allowed number of beads (same or different beads) in a box. From a more
sensible way in the realm of clinical archetypes written in ADL, it is
used to constrain the min and max allowed number of run-time instances
of child nodes of attributes which can be a container such as CLUSTER,
ITEM_TREE, ITEM_LIST, HISTORY and so on.
So far so good but I have a practical problem to model a situation like
the following:
PARENT_NODE (A container type and might not exist or repeat up to 2 times)
a) CHILD_NODE (Must appear once)
b) CHILD_NODE (May appear 0 to 8 times)
So this roughly can be expressed as:
CLUSTER occurences {0..2}
any container attribute cardinality {1..9}
QUANTITY occurences {1..1}
ELEMENT occurences {0..8}
PROBLEM-1: As understood from above description that cardinality simply
depicts the number of instances of subchilds - REGARDLESS of their type
(i.e. QUANTITY or ELEMENT), then above cardinality can be {1..9} or
simply {1..*}. When I examine some sample archetypes such as Line 67 in
autopsy.v1, Line 33 in respiration.v1 and Line 103 in microbiology.v1
the cardinality of container node is {0..1} and they have a number of
child nodes with occurences >0 and it is clear clinically that almost
ALL of those nodes should appear in runtime data. So there is either a
misunderstanding of the use of cardinality here among most of us or I am
totally lost here :)
The above model is expressed in those archetypes roughly as follows:
CLUSTER
any container attribute cardinality {0..2}
QUANTITY occurences {1..1}
ELEMENT occurences {0..8}
QUESTION-1: What is the correct approach for above problem?
QUESTION-2: Assume in some other place in the archetype you reference
the ELEMENT node with occurences {0..8} by use_node. And in this
particular place you do not want to have up to 8 instances and but also
you want it to be mandatory (i.e. 1..) or even want {3..5}. What is the
solution? (other than writing the whole thing once again)
QUESTION-3: Related with second question, I also need to disallow usage
of some values when referencing by use_node entries. This I believe is
not an uncommon requirement in clinical medicine.For me I have an
element with a long list of values of sites of an organ (Esophagus,
stomach, colon and so on) and in many places of an observation these
sites repeat without change so I can reference original. But in some
cases selection of certain site(s) is not logical and should better be
restricted or selection of only one site makes sense. What is the solution?
Thanks and happy new year to all...
-koray
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