Final answer:
The Schilling test is a diagnostic tool used to determine the cause of vitamin B12 deficiency, which can contribute to pernicious anemia. It measures the absorption and utilization of B12 in the body.
Step-by-step explanation:
The Schilling test is a diagnostic tool used to determine the cause of vitamin B12 deficiency, which can be one of the factors contributing to pernicious anemia. The test measures the absorption and utilization of vitamin B12 in the body. It involves giving the patient a small amount of radioactive B12, either orally or by injection, and then collecting urine samples over a specified period of time. If the body is able to absorb and utilize the B12 properly, then it will be excreted in the urine. If not, it suggests a problem with B12 absorption, which could be indicative of pernicious anemia.