What are the tests for anorexia nervosa?

Clinical Diagnosis. An is diagnosed on the basis of a person becoming preoccupied with her or his weight to the point that through food restriction, laxitive abuse, vomiting, extreme exercise or all of the above that leads the person to weight less than 85% expected. There is an intense fear of gaining weight and distorted body image (belief still "fat"). In women, also, lack of periods 3 consecutive cycles.