A black surgery patiennt at Johns Hopkins University is two to four times more likely than a white to be operated on by a surgeon-in-training rather than a staff surgeon, a Johns Hopkins doctor has reported.

In today's issue of the New England Journal of Medicine, Dr. Lawrence Egbert called this an example of "racial inequity" and "the severity of persistent, if subtle, social inequities within established institutions."

A Johns Hopkins spokeswoman reported yesterday that "Johns Hopkins Hospital does notdiscriminate against anyone" Dr. George Zuidema chief of surgery, called the New England Journal article "unscientific" and its conclusions distorted and unsubstantiated.

Egbert conceded that "several factors besides race" may have influenced the selection of a surgeon, since the neighborhood surrounding the hospital is largely black and "resident surgeons are more likely to be available at night and weekends" when area residents come in with emergencies.

Egbert. a part-time associate in the Johns Hopkins School of Public Health, also was an anesthesiologist in the hospital's surgery department, until last November.

His article - written in collaboration with Hene Rothman - was based on a study of more than 3,000 gallbladder and inguinal hernia (hernia of the groin) operations at the famed Balti more hospital from 1952 to 1972 and a further sample of more than 500 operations in October, 1975.

"No consistent change" in the pattern was seen during the two decades. Egbert maintained. But he noted one exception: the October, 1975. data showed that 223 patients whose care was paid for by U.S. and state Medicaid funds were more likely to be operated on by a trainee whether they were black or white.

This means poverty too "influences whether patients receive care by residents or staff," he concluded.

"Residents" are doctors in training - young men and women who have won their MDs and are spending added years qualifying for a specialty.

But a patient's economic status alone does not determine who operates, he added. He pointed to the fact that blacks who paid cash or had health insurance were still far more likely to be operated on by a resident.

At the very onset of his article, Egbert quoted the World Health Organization constitution, which says "the enjoyment of the highest attainable standard of health is one of the fundamental rights of every human being."

"Clearly," he wrote, "if a health service is to be offered, it must be offered equally to all who need it."

"We assume," he also wrote, "that resident surgeons are less skilled than staff surgeons since resident surgeons are in training; the staff surgeons are the teachers of the resident surgeons."

Zuidema disagreed. Hesaid that residents are supervised by either a staff surgeon or a chief resident "who has six to nine years' practice beyond medical school and may well be among the most skilled of surgeons." Many operations are done by chief residents, he said, and no patients receive lower quality care.

Also, he said, Egbert studied two simple surgical procedures. If he had studied major blood vessel or heart surgery, he would have found staff surgeons doing most of the operations, Zuidema said.

Two more Johns Hopkins doctors of the three whom Egbert credited with giving him "challenging ideas" and "charp criticism," also called Egbert's article overstated or unfair.

"I tried to get it toned down because it was unfair," said Dr. Jerome Frank, a psychiatrist well known for his efforts for world peace and racial equality.

Frank and Dr. Donald Gann of the hospital's emergency division said the hospital is in an area occupied mainly by blacks, that the neighborhood residents often use the emergency room for lack of a family doctor. Patients who lack a doctor or come to the emergency room at night are commonly assigned to a resident, they said.

"Most teaching hospitals are organized so cases who come into the clinics or emergench department without a referring physician become cases of the resident physician become cases of the resident staff," Gann said. "That's fundamentally how residents get their cases. whichis how new physicians get trained around the world.