The traditional response, whenever there's a health problem, is to call a doctor. But today, in a growing number of situations, it may make more sense to call a nurse.

The nursing profession has changed tremendously in the last 20 years. Growth in the number of graduate-level nursing programs, and the emergence of nurse-practitioners and other nurse-specialists with advanced degrees, have vastly expanded the scope of services that nurses are prepared to provide.

Nurses are being certified as specialists in community health, care of older adults, nurse-midwifery, care of children, medical-surgical nursing, psychiatric and mental health, child and adolescent health, pediatric nursing . . . the list continues. And increasingly, nurses are working as independent practitioners and entrepreneurs, providing comprehensive care in health maintenance organizations (HMOs), corporate health centers and community settings.

These nurses are meeting an important need. In an increasingly specialized health care delivery system, nurses have taken on a key role in maintaining ongoing relationships with patients and their families. They are in a unique position to provide education and counseling services before admissions and following discharge, monitor progress, notice and respond to problems before they become serious, and refer patients to other health care professionals as needed.

And nurses make house calls.

Two key trends in health care are making home care increasingly important: the aging of the population and a growing emphasis on lowering health care costs. People over 65 are by far the major consumers of home health care service, accounting for 85 to 90 percent of the demand. As the elderly population continues to grow, so will the need for home health services.

Cost, too, is an important consideration. The average cost of a day in the hospital is now between $350 and $400. The average cost of a day of home care is only between $25 and $70. To help contain costs, hospital stays are becoming shorter and shorter -- and the need for qualified home care is escalating dramatically.

Nurse-specialists are able to provide a number of services traditionally handled only by physicians, such as prescription of medications in some states and monitoring of patient progress.

But they are not "little physicians." Their role is, rather, an extension of nursing's traditional role -- patient care. That care takes place before problems occur -- through, for example, patient education to promote stress reduction, smoking cessation, blood pressure control, balanced nutrition or exercise.

And nursing care responds as problems emerge -- through early intervention with nursing home patients and referral to physicians. It responds during serious illnesses -- through ongoing monitoring of conditions and administration of therapeutic regimens. And it follows up once a crisis is past -- through home visits, checkups and family education.

Nurses, in short, are not supplanting physicians. They are filling a widening gap in the health care delivery system, and helping meet the nation's growing need for accessible, affordable care. A recent study found that when home care for children with terminal cancer was coordinated by nurses -- with physicians serving primarily as consultants -- the costs were 18 times lower than for care in a hospital setting.

The need for the kinds of services nurses can provide is clear. Nurses' ability to provide such services cost effectively is proven. But there is a problem: reimbursement for services.

In 25 states, services provided by nurses cannot be covered through insurance, even though the same services are reimbursable when provided by another health care practitioner. In other states, only certain categories of nurse-providers -- such as nurse-midwives, psychiatric nurses or nurse anesthetists -- are eligible for reimbursement.

There are problems at the federal level as well. Nurse-midwives and nurse-practitioners operating in rural clinics are among the few nurse-providers eligible for Medicaid reimbursement.

Outmoded legislation and lack of public awareness of nurses' changing roles account for much of the problem. But there is another issue as well. Health care today is becoming increasingly competitive. Providers at every level of the health care system are seeking to guard their traditional prerogatives and limit service provision by other groups.

This is unfortunate. Nurses are not seeking to expand their range of practice at the expense of others. They are simply asking to be allowed to perform the services they have been educated to provide, and to be reimbursed for those services appropriately.

Keeping outdated policies on the books will not change the nature of today's health care. But it will help keep the cost of health care high, and put ongoing, quality care out of many people's reach.

Eunice R. Cole, RN, is outgoing president of the American Nurses Association.

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