My sister was so nice and gave me her old nursing school books to save me some money. I have been trying to study with her HESI exam study guide from a few years ago, but I have this sick feeling in my stomach. What if they have changed the test since then? I am so scared that I am just wasting my time memorizing outdated information. I really can't afford to buy a brand new one right now. Do you guys think it is okay to use an older guide, or is it too risky?