Samples sizes cannot be negative integers. If not checked at FHIR conformance/validation efforts then thousands of implementers will need to add checks to their systems.

Currently the datatype for the following four elements is set as integer, and we want to change it to unsignedInt:

Statistic.numberOfEvents, Statistic.sampleSize.numberOfStudies, Statistic.sampleSize.numberOfParticipants, Statistic.sampleSize.knownDataCount