More than two decades after Medicaid was launched with the Great Society promise of ensuring "adequate medical care for every citizen," the program falls far short of its goal, concludes a new report by a consumer group.

Not only does the government's health insurance program for the poor exclude between half and a third of all poor Americans, but for the 23 million who are included, coverage is often spotty and varies greatly from state to state.

Mississippi, for example, spends about $100 a year of state funds per poor person, while New York spends about $1,600.

Total Medicaid spending, which includes a federal contribution, ranges from $400 in Mississippi to $3,200 in New York -- eight times as much.

The 257-page report, issued by the Public Citizen Health Research Group, an organization affiliated with Ralph Nader, calls Medicaid a "shaky edifice" that "while improving access to health care for millions of people, has nonetheless proven grossly inadequate and inequitable for millions of others."

The state-by-state analysis of Medicaid, written by Dr. Sidney M. Wolfe and Karen Erdman, poses the question: "If I were a poor person living in the United States, in which state would I have the best chance of gaining access to quality care through the Medicaid program?"

State Medicaid programs were ranked on the basis of five criteria: eligibility requirements (the broader the better), range of services covered (the more the better), availability of doctors and nursing homes (the wider the better), quality control (the tighter the better), and reimbursement rates (the higher the better for physicians; diagnosis-based fees preferred for hospitals).

Breadth of eligibility and coverage were the most important factors in each state's overall ranking.

By this analysis, Minnesota came first with the most comprehensive Medicaid program, followed by Wisconsin, New York, Massachusetts, Connecticut and California. The District of Columbia ranked 11th, Maryland 14th and Virginia 42nd. The five lowest-ranking states, counting from the bottom, were Mississippi, Wyoming, Arizona, Alabama and Missouri.

In general, northern states dominated the top of the list. The highest-ranking southern state was Kentucky, which placed 25th. Medicaid is funded jointly by the federal government and the states. Last year, the federal government spent about $23.4 billion on Medicaid, while the states spent about $19 billion.

It is not surprising that poor states tend to spend less on Medicaid -- and to have weaker Medicaid programs -- than rich states. But one of the more disturbing findings in the new report is that the flow of federal Medicaid dollars to low-income states with large numbers of poor residents does not come close to making up the difference.

Though the federal government by law pays a higher proportion of Medicaid costs in states with a relatively low per-capita income, the new report found that low-income states actually receive fewer federal dollars per poor person than richer states. That is because poor states tend to offer fewer services and are therefore eligible for less federal Medicaid money.

When President Johnson signed the Medicaid legislation into law in 1965, he declared, "Today we expect what yesterday we could not have envisioned -- adequate medical care for every citizen."

But the Health Research Group analysis concludes that "we can neither envision nor expect Medicaid in its present form to be the fulfillment of this promise."

Even in the best-rated states, the report points out, Medicaid is "rife with gaps" in eligibility, coverage and quality control.

Because Medicaid's constituency -- mainly poor people -- lack political representation and clout, they "often become victims of the political process," the report says. In a budget-conscious era, Medicaid benefits are often reduced or eliminated in favor of proposals backed by more powerful interests.

"Medicaid has had its modest successes -- for those eligible and in some states," said Dr. George Silver, professor emeritus of public health at Yale University and a key consultant on the Health Research Group project. But Silver, a deputy assistant secretary of health, education and welfare in the late 1960s, said "the promise of equal access and equitable provision of medical care for the poor of this country continues to be denied."

Besides its analysis of the Medicaid system, the report provides state-by-state profiles of the nation's 51 Medicaid programs, including those of the District, Maryland and Virginia.

The District's Medicaid program is praised for its "decent service package and acceptable reimbursement policies" and its eligibility requirements -- the most liberal in the nation. But the report calls coverage "inconsistent" because the District does not cover drug and alcohol abuse treatment, nurse-midwife services or nonprescription drugs and limits coverage of home care, outpatient mental health care, adult dental care and well-child care. Also, quality control efforts are "minimal," and relatively few doctors are available to service Medicaid patients.

Maryland's Medicaid program, the Health Research Group consultants say, is better than its overall ranking of 14, because of its recent progress and innovative programs. Its coverage is rated "particularly weak" for rehabilitative services, outpatient mental health care, preventive and diagnostic services, home care and drugs. Quality control has been "half-hearted," though Maryland has done better than most states in enforcing nursing home standards.

Virginia's Medicaid program, ranked 10th worst in the nation, is described as "terrible," because of very low income cutoffs, a limited or nonexistent medically needy program, coverage "that cuts corners almost everywhere" and obstacles such as copayments (patients pay a small fee each time they visit a clinic or fill a drug prescription). Virginia has the third-lowest fee schedules in the nation, reimbursing doctors only $7.20 for an office exam of a Medicaid patient, compared with the national median of $30. To assure all low-income Americans an equal right to Medicaid help, the Health Research Group says the federal government should establish uniform standards for eligibility, coverage, quality control and reimbursement in all states. It says the federal government also should assume all Medicaid funding except administrative overhead.

Specifically, the group recommends that a federalized Medicaid program should cover everyone whose income falls below the federal poverty line, after subtracting out-of-pocket medical bills, and pay for all services currently covered by the most comprehensive of the state Medicaid progams.

It is "beyond the scope" of the Health Research Group report to estimate the costs of those proposals, the report says. The usual debate over such costs is misleading anyway, it argues, because the public is already paying for health care of the uninsured poor indirectly through state or local programs or federal subsidies.

What's more, because such treatment is often delayed, it is more complicated and expensive than easily accessible preventive or prompt care would be.

Most observers say large-scale expansion of the Medicaid program is politically unrealistic in an election year and a Gramm-Rudman era of budget-cutting rhetoric.

But in the face of such conventional wisdom and given the price the nation is already paying for poor people's lack of access to comprehensive medical care, the Health Research Group report argues that the government "cannot afford not to expand Medicaid."

RANKING STATE MEDICAID PROGRAMS 1. Minnesota 2. Wisconsin 3. New York 4. Massachusetts 5. Connecticut 6. California 7. New Jersey 8. Washington 9. Oregon 10. Michigan 11. District of Columbia 12. Iowa Maine 14. Maryland 15. Rhode Island Vermont 17. Hawaii 18. Illinois 19. Pennsylvania 20. Nebraska 21. Kansas 22. Utah 23. Montana 24. Colorado Kentucky 26. Georgia 27. Indiana Ohio West Virginia 30. Florida 31. North Dakota 32. Alaska 33. Delaware 34. South Carolina 35. Tennessee 36. North Carolina 37. New Hampshire New Mexico 39. Louisiana 40. Texas 41. Oklahoma 42. Virginia 43. Idaho 44. Nevada 45. South Dakota 46. Arkansas 47. Missouri 48. Alabama 49. Arizona 50. Wyoming 51. Missippi