I don't know where I copied this from:
"i recently spoke with several counselors & psychiatric physicians in charge of an emergency psychiatric in-patient clinic in Texas & posed the question to the following questions to them: 1) in your experience approximately what percentage of the patients who revolve through this ward are suffering from some form of depression? "a very high percentage", "90 percent", & "100 percent" were the replies. 2) since we know that there is a correlation between mood & sunlight exposure, & vitamin d deficiency is known to induce depression in the winter months, why not administer a 25(OH)D test on every patient who comes in? invariably they enthusiastically agreed that this would be a great idea! alas, for the doctors to try this would require the persistent demand for this from every patient in the ward..."