Jose Mejia, left, takes a polygraph exam prior to his appearance on the TV show Nothing

Bogota, Colombia ? Have you ever cheated on your wife? Stolen money from your boss? Do you consider yourself a better person than your mother-in-law?

Coming soon to U.S. television is a game show that has already taken Colombia by storm. Similar productions are being sped up in Brazil, France and Britain. The concept: watch people squirm while they’re being interrogated.

The format of “Nothing But the Truth” is as simple as it is cruel: If the participants truthfully answer 21 increasingly invasive questions, they walk away with $50,000.

Tell a lie, though, and the lie-detector test they took backstage betrays them before a studio audience packed with unsuspecting friends and loved ones.

Caracol TV bought the concept from Los Angeles-based producer Howard Schultz, who also sold a pilot to the Fox network that is expected to air in a few months. In Colombia, it is getting top ratings, and feeding a boom in the use of polygraph tests.

Since the show first aired in May, the phone hasn’t stopped ringing at True Test, one of about 200 companies in Colombia that charge about $65 a test to customers that include airlines, banks, multinational companies – and the occasional bickering couple.

“I went from receiving five inquires a week to ten a day,” said True Test owner Juan Villota. “Pooling together money from all the polygraph examiners in Colombia could never buy you that kind of publicity.”

The truth-be-told boom is surpassed only by the controversy over the polygraph tests, which use a blood-pressure cuff and electrodes to measure changes in a person’s stress level when asked sensitive questions.

An exhaustive 2003 study by the U.S. National Academy of Sciences concluded that the tests have too many false results to be relied upon as job-screening tools.

The American Polygraph Association, based in Chattanooga, Tennessee, says polygraphs aren’t perfect, but are still highly valuable when combined with other vetting techniques. The trade group tried unsuccessfully to get Caracol to pull the program, fearing it could reinforce old stereotypes of the polygraph as a pseudoscientific truth machine.

“It’s the sort of abuse we’ve been trying to stamp out for years,” said Donald Krapohl, president of the trade group, which urges examiners to abide by a strict ethical code that rejects the kind of intrusive questioning viewers see on the show.

But the network stuck by its guns.

“My job is to produce entertainment, not play public prosecutor,” said Cristina Palacio, the Caracol executive who bought the show from Schultz.

To the producers’ surprise, the program has proved to serve as a catharsis for some conscience-plagued contestants.

Schultz, the creator of such reality TV hits as MTV’s “Next” and ABC’s “Extreme Makeover,” said the huge success of “Nothing But the Truth” in Colombia has encouraged networks in other countries to speed production of their own versions.