In view of these serious consequences and the IRS' renewed interest in hospital-based physicians, it is imperative that all hospitals examine their contractual relationships with physicians under the foregoing standards to ascertain whether any physicians are improperly being characterized as independent contractors. Of particular concern are arrangements with aspects similar to those in TAM 9443002. Hospitals operating in states that still prohibit the employment of physicians are not necessarily protected, as the IRS does not accept the corporate practice of medicine doctrine as a defense to characterization of physicians as employees for tax purposes. In those states, it is probably best to handle problematic situations through the use of professional corporations, as discussed above.