Matthew Perrone, AP

A top congressional watchdog is pushing the Centers for Disease Control to do more to catch financial conflicts that could sway the opinions of scientists who make public health recommendations. Republican Senator Charles Grassley sent a letter to the agency last week asking what CDC is doing to better monitor and disclose financial ties of experts who serve on its 17 medical advisory committees.

Grassley cited a report by government inspectors released late last year that found CDC frequently failed to identify and police conflicts of interest. CDC said in a statement that it will respond to Grassley's inquiry promptly, but pointed out that it already adopted some of the report's recommendations.

An agency spokesman said that the CDC adopted a new system for tracking and documenting conflicts of interest in January. “This documentation eliminates ambiguity associated with CDC's conflict analysis and conflict management,” said CDC spokesman Thomas Skinner.

Among other public health issues, CDC's advisers make recommendations on when people should receive flu shots, vaccinations and cancer screening. Although their advice isn't binding, it is generally followed by doctors and hospitals across the country.

In the letter obtained by The Associated Press, Grassley asks CDC Director Dr. Thomas Frieden to turn over all conflict of interest forms submitted by the agency's advisers from January 2008 to present.

In 2007, almost none of the agency's 250 advisers properly filled out forms in which they were required to state financial conflicts, according to the report by the U.S. Department of Health and Human Services' Office of the Inspector General. The report concluded that the CDC failed to follow-up with some of the experts who disclosed potential conflicts. These experts are still allowed to serve on advisory panels, but only after receiving waivers from the CDC.

Grassley has spent the last three years prodding government agencies and universities to disclose their financial relationships with drug and medical-device manufacturers. Those companies are now required to publicly report all gifts and payments to physicians, under a provision of the health care overhaul signed into law last month. Grassley was the chief author of the language, though the Iowa Republican ultimately voted against the bill.

Earlier this week the Food and Drug Administration said it would begin disclosing more details about its advisers' conflicts of interest.