Hospital CNA Test?

Hi, I apply for a position in a hospital and HR said I should stop by to take the CNA test.
Does anyone knows what kind of test this is? I know it may vary from state or hospital, but if you have work in a hospital and had taken this test please let me know what to expect or if I should review any school notes.
any comments will help, I am crossing my fingers.. I hope they hire me.
Thank you, so much!