Almost five years ago, Robert M. Entman of Duke University wrote a guidebook on how President Reagan, then newly elected, could "tame" what he called "The Imperial Media."

Entman suggested, among other devices, keeping most government information officers "in the dark," discouraging them from mingling socially with journalists and using discipline to keep free-lance leakers from getting to the news media.

The Entman formula reads like "a blueprint for the Teflon presidency," in the words of A. Lawrence Chickering, executive editor of the Institute for Contemporary Studies, which sponsored the Entman study.

And although some of Entman's advice was off the mark (he suggested, for example, that a president "not make a fetish of getting on television"), his system also included the important suggestion that a new president could "tame White House beat reporting by decreasing reporters' expectations of full access." A new or popular president could "take advantage of the country's growing preference for strong leadership to legitimize the approach," he wrote.

Only a few White House officials acknowledge knowing about the Entman formula, but Edwin Meese III, who ran the Reagan transition in 1980 and is now attorney general, was said to have used the advice as an early Bible, and former White House communications director David R. Gergen has said he openly opposed it.

Now, however, some reporters covering the Reagan administration say Entman appears to have written some of the golden rules for dealing with the news media.

Mainly, the Reagan team is less afraid to say "no" to reporters. Often politely, but sometimes defiantly, aides refuse to give information that journalists demand, even when they invoke the public's right to know or the clout of the nation's most powerful journalistic institutions.

Riding a wave of public antipathy for the media -- and in some cases encouraging it -- the Reagan administration appears to have succeeded to an unusual degree in selecting the information that goes to the media instead of reacting to reporters' queries.

"Every administration I have been associated with has tried to focus public attention on a given subject, to expose the president in the best light," White House spokesman Larry Speakes said last week. "Any corporation, including media corporations, do much the same thing, try to present their corporations in the best light.

"I would say this administration has been the most accessible as any so far as far as senior policy makers being willing to talk to the press on a regular basis and even a spot news basis," he said, citing the 30 minutes a day that White House chief of staff Donald T. Regan sets aside for reporters.

From the other side of the White House news room a different story comes.

"They pick the story every day. They pick the one that will almost invariably wind up on the nightly news, and that's the one they answer questions on or give access to information about," said Helen Thomas of United Press International, dean of the White House press corps.

"A lot of events, we're absolutely blacked out, and if you don't like it, too bad," she added. "The whole attitude is, 'We will tell you what we think you should know.' "

Although some journalists strongly disagree with Thomas and see the Reagan administration as no different from its predecessors, many others feel as she does.

"There has been a consistent and organized effort on the part of this administration to reduce the flow of government information, beginning with what they consider secret but extended far beyond that," says Bill Kovach, Washington editor of The New York Times.

"There is no area of government where information is not harder to get for us here, harder to get now than it was when I was here in the Nixon and Ford years," Kovach added.

"Their whole attitude is that government information belongs to the government," he said.

Kovach, like others, acknowledged that such complaints might be viewed as the latest "whining" of the media.

And some reporters get around the tactics, and do report some of the crucial internal debates or embarrassments that officials would prefer to keep beneath the serene surface.

Moreover, the Reagan administration has had its share of leakers. In the president's first term, battling White House aides spilled many of their secret battles onto the front pages of newspapers. Big secrets like the clandestine operation to support Nicaraguan counterrevolutionaries also leaked. The Reagan administration cannot be described as totally closed off from public -- or media -- scrutiny.

Still, the attitude toward the media and the level of discipline of this administration to get out its story appear to be on a different scale from its predecessors.

In contrast to reporting during previous presidencies, journalists said they often have less access to that mid-level of the bureaucracy where specialists can explain or amplify decisions made at the top.

"The people hardest to get to now are the worker bees," said ABC correspondent John McWethy, who covered the Defense Department until moving to the State Department. "They kick you up the line until you get to somebody who doesn't know what they're talking about or who's a political operator.

"The top two guys -- Defense Secretary Caspar W.Weinberger and Secretary of State George P. Shultz -- deal extensively with the press. They talk to you all the time, but a lot of the time, they say nothing, nothing at all. What they are trying to do is plug the information gap from the top," McWethy said.

A number of veteran reporters expressed similar views but said their complaints are often met with shrugs from the administration and hostility from the public. They say that closing out the press is not viewed as cutting off an agent for the public but as barring the door against an alien or negative force in society.

As White House science adviser George A. Keyworth put it in a February interview, the American press is "drawn from a relatively narrow fringe element on the far left" that is trying to "tear down America."

Speakes responded, "Neither the president nor I would use those words, approach it in that way."

The challenge to journalists' patriotism is particularly galling to many reporters who see it as an effort to tag criticism of the administration as not merely adversarial but un-American.

"Somehow we're suddenly the enemy -- we're representing the Sandinistas, representing the Soviet Union -- and that just doesn't make sense," said Gregory Nokes, diplomatic correspondent for the Associated Press. "We're part of America, too. We go to church; we go to the softball games; we pay our taxes and serve our time in the military."

Reagan is not the first to try to tame the media. John F. Kennedy is thought to have been the first president to try to control what his minions said to the media by asking an information officer to be present when a reporter interviewed a defense official, now a standard protective device elsewhere in government and out.

Lyndon B. Johnson tried to get the Freedom of Information Act killed in Congress; Gerald R. Ford vetoed amendments that would have strengthened it. Jimmy Carter chafed at leaks and tried several methods of stemming those that were embarrassing or counterproductive, generally to no avail.

But the Reagan administration appears to have been more successful. Perhaps the strongest efforts to slow unauthorized leaks to the media have come in intelligence, defense and national security agencies.

Paul Bedard, who writes for the Defense Week newsletter, said details about defense matters often are so closely held that "I can't even get information that is favorable to them."

But Bedard said one of the more bizarre aspects of this secrecy is that on more than one occasion, Pentagon officials have been unwilling to talk about what has been said in a public hearing.

Cheryl Arvidson, who covers the U.S. Information Agency for Cox Newspapers, said that trying to get even routine information about Charles Z. Wick has been frustrating.

"I wanted, for example, to find out why he didn't have a war record. It got to be pretty humorous because here's this patriot with no service record, but when I called the public information office, they basically told me to buzz off," she said.

Arvidson said she finally told a public information officer: " 'Look, I don't want to write a story that suggests this guy is a draft dodger. That is not what I am trying to do. You are beginning to suggest to me that there is something wrong here.'

"Finally they sent word that he'd been called up twice and failed his physicals," she said. "Just normal press inquiries like that, it's strange to have to go to such extremes."

Nina Totenberg of National Public Radio and David Lawsky of United Press International have been trying to get someone at the Justice Department to explain why a polling place in Selma, Ala., was moved to the county courthouse, a place that has strong negative memories for many blacks.

Totenberg informed Meese at a news conference that she would ask about it at the next news conference. When she did, Meese answered that the change was because voters had access to more parking space, among other reasons. Asked why then the turnout in that district had dropped by one-third, Meese referred the question to the Civil Rights Division where both Totenberg and Lawsky said they found no one willing to give any elaboration beyond the parking problem.

"Civil Rights said that they had a policy of not explaining those things," Totenberg said.

The Reagan administration has sent out a variety of signals that free-lance leaking can be dangerous. Early efforts at using polygraphs to invesvigate leaks helped send the message. A Navy employe who gave photos of a Soviet aircraft carrier under construction taken from a space satellite to a British magazine has been charged under the 1917 Espionage Act.

At the Department of Health and Human Services, the top public affairs official is to be informed "in writing of all interview requests regarding the national media." Said one administration official dealing with reporters: "These guys know they don't get into trouble if they hide from the press."

Investigative reporter and author Seymour Hersh says all administrations have tried to shut out reporters, but he suggested there is now a virtual paranoia about showing any links to journalists.

In some cases the Reagan administration has given tangible evidence of its view of the media, for example, by barring reporters from the invasion of Grenada, an act that caused an outcry from the media and a wave of congratulations from the public.

Another strong message sent to the bureacracy came in March 1983, when the White House issued its National Security Decision Directive 84 (NSDD 84) suggesting that anyone with access to sensitive information would have to sign an agreement for lifetime government censorship of their public statements and writings. The directive also set out guidelines for using polygraph tests for employment and to investigate leaks.

The directive raised so much controversy that the administration has kept it on hold. But "NSDD-84 was still a very effective symbolic measure," said Bruce W. Sanford, a lawyer for Sigma Delta Chi and other journalists' groups.

The Freedom of Information Act, which has weathered major legislative assaults, also works differently under this administration, various journalists and researchers said. In general, they said that as much information may be released as during previous administrations, but not as easily, as swiftly or sometimes as cheaply.

Said William Arkin, a defense expert and journalist with the Institute for Policy Studies, who says he gets information but more slowly, "The mood of the people processing the FOIA has changed. If you're a bureaucrat, you know quite well that your job is to ensure that information is not declassified."