Using websites like Yelp, people can look up ratings and reviews for virtually any restaurant or bar. But what about hospitals, where the quality of treatment is far more important than checking whether the Caesar salad is any good. On Wednesday, a new website premiered that lets you check how good a hospital is. But instead 0f relying on reviews by the public, it rates hospitals based on data from the Center for Medicare & Medicaid Services, or CMS, which collects information about all medical facilities that receive Medicare or Medicaid funds.