You can do arithmetic operations such as sum and average on the columns of a question group.

In this example, the derivations of the questions shown to the right of the question group are as follows:
|
Question |
Derivation |
|
NLesions |
count( LesionVol ) |
|
MinVol |
min( LesionVol ) |
|
MaxVol |
max( LesionVol ) |
|
AvgVol |
average( LesionVol ) |
Note that the count function returns how many known responses there are for that question.
Click here for more help on using set functions.