Robert Frederick Schilling, M.D. (1919– 30 September 2014) was a physician best known for his research on Vitamin B<sub>12</sub>. Schilling was a Professor Emeritus at the University of Wisconsin. He is the namesake of the Schilling test.
Schilling received his medical degree from the University of Wisconsin-Madison in Madison, Wisconsin. He received postdoctoral training at Philadelphia General Hospital in West Philadelphia, Boston City Hospital in Boston, and at University of Wisconsin Hospital in Madison, Wisconsin.
His work on detection of radio-cobalt-labeled B<sub>12</sub> in the urine led to a test for vitamin B<sub>12</sub> absorption named the "Schilling test" in his honor. The Schilling test determines if a patient has pernicious anemia, a disease caused by malabsorption of B<sub>12</sub> due to lack of intrinsic factor. The Schilling test in a second stage may also be used as a control test for other causes of malabsorption of Vitamin B<sub>12</sub> even if it is bound to intrinsic factor (B<sub>12</sub> deficiency which is not pernicious anemia).