A federal retirement agency approved nearly 100 percent of disability claims filed by workers for the Long Island Rail Road even after enacting changes meant to address chronic abuse of the public benefits system, a government review has found.

The agency, the Railroad Retirement Board, which is the equivalent of Social Security for railroad workers, said last October that it would use greater oversight to examine claims filed by L.I.R.R. employees after reports in The New York Times that virtually every career L.I.R.R. employee applied for and received disability payments from the federal government.

But in the six months since the changes were adopted, the agency approved 64 of the 66 occupational disability claims filed by retired L.I.R.R. workers, according to the review, an audit by the Government Accountability Office that is to be released on Friday. A copy of the report was obtained by The Times.

The approval rate was roughly 97 percent, about the same level as before the new measures were enacted.