A group planning to protest the suspension of federal funds to a brain-trauma research laboratory called off its march yesterday after being convinced by Health and Human Services officials that there are serious flaws in the way the laboratory conducts experiments on animals.

Last week, after a four-day sit-in by animal rights activists at the National Institutes of Health, HHS Secretary Margaret M. Heckler ordered a halt to NIH funding of research at the University of Pennsylvania Head Injury Clinic. An NIH investigation indicated that researchers had not used proper anesthesia or sterile methods in brain-trauma experiments on monkeys.

About 100 members of the Boston-based National Head Injury Foundation, angered at what they believed was a lack of commitment at HHS to animal research, planned to march yesterday on the HHS building on Independence Avenue. But group leader Gerald W. Bush called off the protest after meeting with members of Heckler's staff.

Bush said afterward he is convinced that Heckler supports animal research and was right to suspend funding to the laboratory.

"We had a deep fear that the secretary's actions would do more to slow or stop the kind of research that gives us hope," said Bush, whose 23-year-old son is a head-injury victim.

Bush said his group initially believed that Heckler had given in "to the demands of a handful of opponents of animal research." But, said Bush, "we now believe that is not the case . . .

The National Head Injury Foundation represents head-injury victims and their families.

"We are the people with first-hand knowledge of what research has done for our loved ones . . . But if there was abuse at Penn, they should be chastised and should be made to clean up their act."

On Wednesday, University of Pennsylvania officials issued a statement saying they will stop head-injury experiments on monkeys until an evaluation of the research is completed and any procedural problems are corrected.

Spokesman Virgil Renzulli said the university hopes to have a preliminary report on its actions to correct research deficiencies by Aug. 1.

Don Rheem, Heckler's executive assistant, said after the meeting with Bush that Bush had been misled by media reports stating that there was a cause-and-effect relationship between the protest by animal rights advocates and the funding halt.

NIH officials said the investigation into the laboratory was completed one day ahead of schedule because of the protest and said Heckler's decision was based on the investigation's findings, not on the protest.