Dr. Adam Wilson -- a real doctor, an assumed name -- is an obstetrician in Washington and its suburbs.

He will earn about $145,000 in 1978, before taxes. He works 60 to 70 hours a week. He drives a Pinto and a Cadillac and lives in a $200,000 house in an expensive suburb.

Like most doctors in private practice, he is incorporated. This means taxes on 30 percent of his income can be deferred until retirement.

He currently charges $800 for prenatal care and an uncomplicated delivery, $1,000 for a complicated childbirth, $1,100 for a cesarean, $1,000 for a hysterectomy, $450 for a tubal ligation and $350 for an abortion.

And he thinks he is worth every cent.

In this way and many others, he is typical of his thousands of medical colleagues in practice throughout the United States.

Wilson is, in fellow doctors' language, a "good earner." But he is not really a "big hitter": one who, by slave-like hours or great skill or popularity or an extra-lucrative specialty, earns $200,000 or $300,000 or more a year.

Do some doctors do too many operations and tests? Do some do them to help line their pockets?

"Yes, some do these things," he said. "I don't."

He "probably" makes some money, "not a lot," when he gives laboratory tests, he said. And he admitted that "if a patient is covered by insurance, a doctor is a little less reluctant to do all the tests. I've seen time and time again a willingness on physicians' part to order procedures if the insurance covers them, and reevaluate the need for them if it doesn't."

But he strenuously defended his income and his way of practice.

He said he takes pride in "spending a lot of time with my patients," and "making sure I answer all their questions" and do a good job. He said "I know a lot of doctors," and, despite some "bad behavers," most can honestly make as as good a case.

As to income, "I will be grossing around $277,000 in 1978," he said. "I employ five people, three of them full time. I pay out salaries, pensions, profit-sharing, office expenses. After taxes, I'll have about $66,500."

"I am constantly aware of the financial status of my practice," he reported, because "I have to be." He does not take Medicaid patients, because "Medicaid won't pay me what I ask" to do a good job.

He owns a vacation condominium, and has "some investments" and also some debts. He did not want to detail either, because they might reveal his identity.

Like many doctors, he maintains two offices. "For my patients' convenience," he said. But he knows some patients would go elsewhere otherwise.

He sees "about 30 patients a day." This is not an inordinate number, considering that some doctors with efficient employes and a good assembly line see 50 to 60. His work week is longer than the reported 54-hour average for obstetricians, and "there's never a day of the week on which I don't see some patients," he said.

All in all, he argued, "The great majority of physicians are either underpaid or fairly paid. That includes me."

"I spent four years in medical school," he explained. "It was awfully hard. And we were all poor.

"I had a year's internship, at $100 a month, then three years of residency" -- at $3,200 to $10,000 a year, the high years on military duty. "Then, at age 34, ten years ago, my first job, in a clinic, at $20,000.

"I was making $75,000 before I left. One reason I left was the way I saw some of the fellows jack up their X-ray and lab work. We were credited with a share of the income from every test.

"Today, I'll admit, I'm doing all right. But I have a close friend who's a business executive. He's probably not making as much as I am, but I started late and my earnings will go down as soon as I can't see so many patients.

"Remember, I didn't even live in the black until I was 32. I have a very short earning period. So I doubt that my lifetime earnings will ever exceed his."

He said: "Believe me, there are a lot of hard-working doctors who make much less than I do. But the average physician, with his intellectual ability and motivation, could certainly be in some other work where he would be doing very well."

The statistics on other workers, however, say: not quite as well.