I am trying to assess the reliability and validity od a Stroop test. Which is broken into three parts. One where the person names colour words, names colours seen and names colours on congruent or incongruent words. Each category has 96 stimuli or items they respond to.

So my question is how do I calculate the sample size to test the needed number of participants to know the reliability and validity for such a type of test. It isn't like a questtionaire where each question is different. Each item looks the same. This test measures how many items that can be answered in a time limit of 45 seconds.

Any assistance is appreciated.