The Expression Builder is a tool for helping you construct terms in the Arezzo data language. The Arezzo toolkit is used within MACRO to parse and evaluate the rules to be applied during data collection. An Arezzo term can define the rules for a condition (e.g. a data validation condition) or the calculation required for a particular value (e.g. the value of a derived question).
You will use Arezzo expressions in the following places in your study:
validation conditions
validation messages
derivation expressions
labels
question and group skip conditions
lab test question dates
labels
gender
date of birth
uniqueness checks
eligibility conditions
identifier prefix and suffix
In all of these places you can type Arezzo expressions into the relevant field, or you can launch the Expression Builder wherever you see this button
Please note that the Expression Editor used to define events and subject groups differs slightly from the one in the Study Definition module. It includes an extra Study dropdown list and does not check for question type or the existence of a question although it does include the usual checks for expression syntax.