Looking at I_EHR and I_CONTRIBUTION there are two operations to get a set of CONTRIBUTION that are basically the same, but one has a time interval filter, and the other one has pagination parameters.
I think would be simpler to have just one operation to get CONTRIBUTIONs, on either interface, and merge the current filters and pagination parameters into that operation.
As a general design criteria I would suggest to have just one operation per business goal (e.g. get CONTRIBUTIONs).
Seen on the updated spec, there is only a I_EHR.contributions that returns the I_EHR_CONTRIBUTION, and that interfaces is the one that has the operation to list the contributions.