I need help to use Naegele’s Rule to calculating estimated date of confinement

Hi, I need your help ASAP to use Naegele’s Rule to calculating estimated date of confinement.

The due date or expected date of confinement (EDC) can be calculated using Naegele’s Rule. Begin on the first day of the last menstrual period (LMP), subtract 3 months, add 7 days, and then add 1 year.

LMP: February 14, 2015
Subtract 3 months (Great Scott x 3): November 14, 2014
Add 7 days (N-A-E-G-E-L-E): November 21, 2014
Add 1 bear (year): November 21, 2015

How can I apply this rule in Kobotoolbox?

Best regards.

I tried it using another method to calculate estimated date of confinement, it worked! But I had an error message “No partial converter found for type: java.lang.Integer”.

The formula it is ok. But I don’t know why I get that error on Android devices.

screenshot attached.

Welcome to the community, @echavier! Have you validated your XLSForm through this online validator? The online validator should give you some clue with the syntax issue you should be having.

Thanks Kal!

The online validator works great!