Does anyone knows what observation code is used if a patient goes to get a test done for Adult Growth Hormone Deficiency (AGHD)? Either an Insulin Tolerance Test (ITT) (80435) or a Glucagon Stimulation Test (80430) - the patient may be admitted for observation but only as an outpatient. Does anyone happen to know the observation code that's used? (it was told me that it would be a code that captures 23 hours observation)