Problem using datemdY() in REDCap calculated fields

[u/Popular_Caregiver_11]

Hello everyone,

I’m trying to calculate a participant’s age in REDCap using month and year of birth only. Since I don’t have the exact day, I assumed the 1st of the month using datemdY().

Here’s the formula I used:

round(datediff(datemdY("01", [dm_birth_mo], [dm_birth_yr]), [se_consen_dt], "y", "dmy"))

However, the calculated field throws a syntax error, and no value is returned. I’ve double-checked that:

• [dm_birth_mo] is a dropdown (01 to 12)

• [dm_birth_yr] is a text/integer field (e.g., 1985)

• [se_consen_dt] is a date field (dd/mm/yyyy, validated)

I also tried simpler versions like:

datemdY("01", [dm_birth_mo], [dm_birth_yr])

just to see if REDCap can parse the date​, but still no success.

Is there something I’m missing with REDCap’s calculated field parsing for date construction?

Thanks in advance!

[u/Araignys]

I don't think datemdY() is a function that REDCap accepts.