Rationed health care, in which you may not be eligible for a service that you want or need, is a scary prospect, and it's often treated as an inevitable consequence of reform. As it turns out, the U.S. already had rationed health care before any health-care reforms laws took effect; insurance companies do the rationing.
Consumer protections in the new legislation prohibit insurance companies from denying coverage based on a pre-existing condition (as well as mental health or substance abuse), revoking coverage when someone gets really sick or capping annual expenditures, thus forcing families to choose whether to pay their medical bills or their mortgage.
In addition to tighter controls on health insurance companies, the law established a nonprofit research institute, the Patient-Centered Outcomes Research Institute, and tasked it with determining the comparative effectiveness of medical procedures and treatments. The institute is comprised of doctors, hospital officials, drug and medical device manufacturers and various health experts, and it evaluates whether certain treatments are worth the cost in comparison to other alternatives. The institute's research comes into consideration when deciding what treatments should be covered, but it can't be the only criteria for denying service. To what extent the institute's research and recommendations will be used remains to be seen.