What validation rules can I create on questions?

The validation rules that you can create depend upon the question type, such as Numeric or Text.

Question	Validation rules
Age	Acceptable range of numbers for age. Allowed date range for date of birth.
Date/time	Format for collecting date and time. Allowed date range.
Drop-down	Number of options to select in a drop-down list. Answer that users must select to continue with the visit.
Numeric	Number of values allowed after the decimal point. Unit of measurement. Acceptable range of numbers.
Text	Number of allowed characters (up to 4,000). Type of allowed values (either alphanumeric or text only).