The Federal income tax deduction for expenditures on health insurance (one half of such expenditures up to a maximum of $150) and other medical expenses in excess of three percent of income. In effect, the only national health insurance program in the United States, with a deductible of three percent of income and coinsurance of one minus the marginal tax rate. Xo standards are set for what type of health insurance must be purchased if expenditures are to be deductible. Deductible medical expenses are very broadly defined including the services of physicians, dentists, podiatrists, optometrists, chiropractors, and Christian Science practitioners; and equipment, drugs, supplies, and special diets prescribed by such people.