How do you decide when to initiate medical workup (e.g., thyroid, B12, infection) in a geriatric patient experiencing new onset or worsening low mood?  

It is important to distinguish between low mood, which can occur from a host of environmental stressors, and frank depression, and there are 3 ways to look at either in the older patient: Early onset depression in someone now older, and the patient feels the present one is exactly the same as previ...