Princeton Review has used score increase claims on their advertising for years. Kaplan (a competitor) registered complaints asserting that “Princeton Review had no basis to talk about score gains because the start point for measuring gains was generally determined by diagnostic tests, while the end point was a live test. Critics have said that they believe test-prep companies’ initial tests yield low results, encouraging people to sign up for courses and to credit the companies for large gains later”. This information comes from an article in USA Today