Laboratory tests are medical tests that are conducted in a controlled environment, typically a laboratory setting, in order to diagnose, monitor, or screen for diseases or conditions. These tests can involve analyzing blood, urine, tissue samples, or other bodily fluids or substances to measure levels of certain chemicals, cells, or other elements that can indicate the presence of a particular condition. Some common types of laboratory tests include blood tests, urine tests, and tissue biopsies, among others. These tests are an important tool in healthcare for helping clinicians make accurate diagnoses and develop treatment plans for patients.