Several studies show that hospital staff often order too many laboratory and x-ray tests. The excessive test ordering adds unnecessary costs and sometimes results in false-positive findings. Researchers and managers have tried to change the test-ordering behavior of health care providers, but it is not easy. Providers are increasingly using computer-based systems to automate orders for tests, medications, and referrals. These systems are called care provider/computerized physician order entry (CPOE), and it ensures legible, standardized orders. It can be linked with software that provides staff with important information about tests or drugs, such as abnormal values, costs, and drug interactions. It may also include reminders or alerts to help assure that orders are appropriate on the basis of previous orders, medications, and patients' diagnoses. Given these features, hospitals are beginning to test ways of using CPOE to improve provider test-ordering behavior.