Regulators still are finding a high level of serious deficiencies in the work of major audit firms, continuing a trend begun last year, a member of the U.S.'s audit-industry oversight panel said.

Most of the Public Company Accounting Oversight Board's 2011 inspection reports of the biggest firms have yet to be issued, but they will show a continued "spike" in audits found to have serious problems, PCAOB member Jeanette Franzel said in a speech in Chicago on Thursday.

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