Federal employes who lost their jobs because of reductions in force (rifs) last year received only "limited assistance" from the government in finding new jobs, according to a new General Accounting Office report.

The study, requested by Rep. Geraldine A. Ferraro (D-N.Y.) and based on a survey of federal workers who received specific rif notices, says that riffed workers were more successful in finding jobs on their own than in relying on federal placement programs.

About 44 percent of the 500 employes who responded to the survey said they had not registered for the Displaced Employe, Voluntary Interagency Placement or Federal Employe Re-Employment Registry programs operated by the Office of Personnel Management. Only 10 percent of those who registered in any of the programs actually got a job offer, according to the GAO.

And, despite efforts to publicize the various job-hunting assistance available in the agencies, GAO found that 24 percent of the employes said they had never heard of any of the placement programs.

The GAO report also restated earlier findings that rifs "are very disruptive and costly, and should be avoided if at all possible." Based on its sample, it estimated that severance pay, unemployment benefits and lump-sum leave had cost the government at least $20 million for employes terminated by rifs in fiscal 1981.

OPM Director Donald J. Devine challenged the GAO findings, saying the report "lacked any historic or government-wide perspective" on rifs. He said the Reagan administration had accomplished 90 percent of its personnel reduction goals through attrition, a much better record, he said, than when the Eisenhower administration fired 100,000 persons in the 1950s.

Devine also complained that the GAO survey failed to take into account the number of employes who were helped in finding jobs after they received general rif notices, usually agency-wide alerts that are distributed 30 days before dismissal. Specific rif notices don't have to be given until five days before dismissal.

"Obviously we can't place many people in five days," said Devine, who credited the placement programs with helping to find jobs for employes "before" they were given specific notices.

OPM has said the programs placed 7,576 employes in jobs during fiscal 1981. But the GAO report called the number "misleading" because OPM failed to clearly define "placed" or to make distinctions between those who found jobs through the program and those who found jobs on their own. Also, according to GAO, there were some cases in which both agencies and OPM "double-counted" the same placements.

Devine defended his agency's efforts to inform employes of the programs, saying OPM had distributed "tens of thousands of brochures," made on-site visits to agencies and trained 2,000 personnel officials about the new placement programs. He also dismissed criticisms of OPM's placement record-keeping.

"The point of the program is not to count people but to place them," he said.

More than 4,400 employes lost their jobs, retired or resigned because of rifs during fiscal 1981, according to OPM. In addition, 4,700 were downgraded, reassigned, furloughed or had their duties changed. OPM had estimated that 8,000 more employes would lose their jobs during fiscal 1982; figures for that period, which ended Sept. 30, have not yet been compiled.