Why was the result ‘Invalid’?

An Invalid result is generated when a player taps the screen too many times, or when the responses are highly inconsistent.

If an invalid result occurs, the player should be retested under close supervision in a quiet environment. This should ideally be done 24 hours after the first test (or after a break if circumstances don’t allow for retesting on another day).

NOTE: One credit allows you to test an individual up to four times.