Using CDC reference ranges in development version

[arjunchandna]

We used the CDC reference ranges for our project and got good results for wfaz scores. Would be great to see this integrated into the substantive package. Happy to provide data / further feedback if helpful.

[ernestguevarra]

@arjunchandna thanks for the feedback.

We have sent this out to folks who have initially requested for this additional feature for them to test but have had a long gap of no communications from them and we wanted to make sure we are getting this correctly.

One issue we have is that we don't have real world data for older age groups to use for our testing suite for the new function. We believe this is important so that we can include a full test suite similar to what we are using to test the WHO GS standards function.

This development version exists and is usable from GitHub. So, people can still use this as is. We would like to get this onto CRAN for the new version this year one we are able to fully test.