WASHINGTON: The military trainers who came to Guantánamo Bay in December 2002 based an entire interrogation class on a chart showing the effects of "coercive management techniques" for possible use on prisoners, including "sleep deprivation," "prolonged constraint," and "exposure."

What the trainers did not say, and may not have known, was that their chart had been copied verbatim from a 1957 Air Force study of Chinese Communist techniques used during the Korean War to obtain confessions, many of them false, from American prisoners.

The recycled chart is the latest and most vivid evidence of the way Communist interrogation methods that the United States long described as torture became the basis for interrogations both by the military at the base atGuantánamo Bay, Cuba, and by the Central Intelligence Agency.

Some methods were used against a …