The focus on the nation's deep recession in the fall congressional campaign has largely muffled debate over the question of who has benefited and who has lost from the Reagan economic program.

Despite gains in reducing inflation, the president's tax and budget proposals have not achieved their goals of recovery. But they have successfully altered government policy toward income distribution, both among different groups of people and among different regions of the nation.

There are three basic findings resulting from studies of the distributional effects of the Reagan program:

* The largest share of the benefits, mostly tax cuts, has gone to the very rich, and the largest burden of the cuts in domestic spending has fallen on the poor, particularly the working poor.

* The middle class has a net gain from the budget and tax cuts, although the gains are, except for those in the upper ranges of the middle class, largely eliminated by the effects of bracket creep, inflation, Social Security tax hikes and the recession.

* The combination of domestic spending cuts, military spending increases and tax cuts will widen disparities between the affluent Sun Belt states and the poorer Frost Belt regions, with Texas and California as the major gainers.

These findings are the battleground between philosphic notions of equity and fairness and economic concepts of efficiency and effective use of resources.

The administration has, for example, adopted strikingly different, if not diametrically opposed, policies to encourage work, productivity and savings for different income groups.

For those in upper income brackets, the Reagan administration has provided major tax reductions on the theory that the beneficiaries will be encouraged to work harder, make more money, and invest their new income in investments and savings that will promote the national good.

For the working poor, those who had marginal jobs and qualified for partial food stamp and welfare grants, along with Medicaid coverage, the policy has been to encourage increased work by eliminating eligibility for government support.

These issues are related to, but separate from, the second basic question when evaluating the Reagan program: has it worked? In his first months in office, President Reagan made a series of promises and predictions:

In February, 1981, he told Congress that if his budget and tax legislation were "enacted in full, this program can help create 13 million new jobs, nearly 3 million more than we would have had without these measures." As of September, 1982, there were 200,000 fewer jobs than when he took office.

He also said: "Our tax program will, if enacted, have an immediate impact on the vitality of the nation," but industrial growth has been stagnant. He told the nation: "Deficits will get smaller until in just a few years the budget can be balanced," but now the projection is for deficits in excess of $100 billion for the foreseeable future.

On the other side of the coin, the rate of inflation has been halved, and the reduction has exceeded administration predictions. Interest rates are, for now, coming down. The stock market has moved sharply higher during the past two months, and the administration contends that the rise is a harbinger of economic recovery. These issues have been grist for the congressional campaign that comes to a close this week.

The separate distributional issues concerning who has gained and who has lost as a result of the program have been studied by a number of groups, including the Congressional Budget Office (CBO) and the Urban Institute. There is some variation in the details of the findings, although there is general agreement about the trends of the Reagan program.

In a February, 1982, study, the CBO attempted to analyze the distribution of the burden of the 1981 budget cuts and of the benefits of the 1981 tax cuts among five income groups.

By 1985, the CBO concluded, 45.2 percent of the total reductions in benefit programs will be borne by households making less than $10,000, and 26.1 percent will fall on those making from $10,000 to $20,000. In contrast, households making from $20,000 to $40,000 will absorb 19.4 percent of the cuts; those making $40,000 to $80,000 just 8.7 percent; and the top bracket, $80,000 and above, less than 1 percent of the cuts.The CBO then combined cuts in direct benefit programs with reductions in such "in kind" programs as Medicare, Medicaid and Guaranteed Student Loans and the benefits resulting from the tax cut. In this case, net household income changes as follows by 1985:

For the household making less than $10,000, there will be a net loss of $140 in income. For the household making $10,000 to $20,000, there will be a net increase of $560 in 1985, and for the $20,000-to-$40,000 household, the increase will be $1,540, growing to $2,990 for the $40,000-to-$80,000 household. For the top category, $80,000 and above, the net household income gain will be $21,860.

The Urban Institute performed a more sophisticated study that attempts to analyze in more detail how different categories of poor persons are affected by the budget and tax cuts, and to incorporate the effects of inflation on the value of tax breaks. The 1981 tax bill did not change the value of the personal exemption, the standard deduction and the earned income tax credit, the provisions most important to persons in the lowest tax brackets, and consequently inflation is forcing a decline in value of those breaks until 1985, when the exemption and standard deduction are to be indexed.

The study found that when calculating changes in family income resulting from administration-passed cuts in taxes, food stamps and the Aid to Families with Dependent Children program were combined, the poor lost money and the rich gained in comparison to the rest, both in terms of percentage gain and dollar gain.

"The direct short-run effects of the policy changes are to the advantage of the rich and to the disadvantage of the poor and have modestly benefited the middle class," the study found.

Among the poor, however, the study found that almost all the cuts were falling on those who have some private earnings, since a basic mechanism for savings used by the Reagan administration has been to reduce or eliminate incentives to work under which beneficiaries did not lose a dollar or more of welfare, food stamp and medical coverage for every dollar earned.

In a second analysis of the Reagan program, the Urban Institute evaluated the regional and state consequences of the spending and tax cuts and the military spending hikes. In this case, the study found:

"On the whole, President Reagan's policies will widen economic and fiscal disparities between wealthy and growing states, on the one hand, and less affluent and less economically vital states, on the other hand . . . On balance the changes add further fuel to the 'Sun Belt-Frost Belt' debate and raise more fundamental questions about the extent to which federal policy should more explicitly take into account its regional fiscal impacts."

While the pattern is not absolute -- New England, for example, benefits significantly because of its defense production facilities and gets a high percentage of the tax break because its residents are relatively well off -- the major benefits of the program will go to the Southwestern and Pacific states.

While the average per capita benefit across the country of the Reagan tax and spending programs is $65, California, for example, will get a per capita increase of $145 and Texas $127, in part because both states have major defense production facilities.

Arkansas, in contrast, will sustain a net per capita loss of $38, while such states as Iowa and New York will pick up far less than the national average, $36 and $33 per capita, respectively.

On the campaign trail, however, the distributional questions raised by the Reagan administration's programs have been submerged in large part by the partisan calls of either "stay the course" or "it's time for a change."