dhis2-devs team mailing list archive

[Jason Pickering <jason.p.pickering@xxxxxxxxx>]

>> It is still not clear to me how the
>> multidimensional data elements are used to calculate indicators in the
>> same was as PODE (plain ol,d data element).  I guess this is handled
>> somehow by the API?

>> I have not played around with this, but I suppose it is possible
>> somehow from wihtin the  indicator definition panels.

Well, I have now played around with it and see more or less how it
works. I have promised Lars I would try and put together some more
documentation on the multidimensional data elements funcitonality,
which I will try and distill together out of all these mails. But
first a few more questions.

Once I define an data element (Clinical Malaria) with Cateogries (Age
(3 cateogory options) /Gender (2 cateogory options)) I get six data
elements in my entry screen corresponding to the combination of all of
these. When I go to define an indicator (say Malaria incidence for
under 1), I can select these "sub-elements" . So for the numerator I
get something like

Clinical Malaria (Under1, Female,) + Clinical Malaria (Under1, Male,)

and for the denominator, I would choose a semi-permanent data element
like population..

Age Under 1

That is pretty sweet and I can calculate a Clinical Malaria under 1
incidence rate, so defining inidcators with multidimensional data
elements seems to work fine (have not tried to calculate anything but
I guess this works as well).

Anyway, my first question is about that last little comma. It would
seem somehow (I have not looIked at the code) that there are
three-dimensions that are sort of hard-wired. I have only defined two.
Is that last comma significant, or just a bit of screen lint?

Now, my next question which is a bit more erudite. Supposing I would
go down the route of defining all of my indicators in a
multidimensional fashion, is there any limit to the level of
dimensionality that I can assign them and where should I start? Lets
think about the malaria data element

For malaria I might decide to get very complicated and choose many
categories and options (Cateogories are after the number, possile
cateogry options are in parentheses.

1) Type (Disease, Service delivery, equipment)
2) Disease type (Communicable, Non-communicable)
3) Transmission method (Vector Borne, Water borne, Air borne, Sexually
transmitted)
4) Disease (Malaria, Leprosy, Leishmaniasis, etc)
5) Diagnosis status (Clinical, confirmed)
5) Patient status (OPD, IP, Deaths)
6) Age (Under 1, 1-5, Over 5)
7) Gender (Male, Female)

This list is not complete, and would need some more category elements
to be totally complete, but this enough to get started. So, I can see
that if I define my categories and options like this, I will get a
data element for "OPD Clinical Cases of Malaria Under 1" at some
point.

So, I guess my question is, where do i start to define my data element
dimensionality? With Disease? There are dimensions "above" the disease
however like I indicate here, like the transmission method. What if I
want to be able to know the total number of cases of all vector borne
diseases? Not a totally unusual request. Would I need to start the
definition of my data elements from there? Would this need to be a
"Dataelement group" instead? What about if I need to know the total
number of cases of communicable diseases? Would this not imply I would
need to add this data element to two seperate data element groups,
which at least with DHIS 1.4 is a no-no as it results in duplicates in
the PivotTables?

It seems like we have stumbled on a partical accelerator. The deeper
you dig, the more dimensions there are.

Any practical suggestions. I know this is yet another erutdite
example, but it highlights that if we are going to have
multidimensional data elements, we need to be able to provide guidance
on how they should be setup.

Best regards,
Jason