But such tests aren't unique to Disney. MGM/United Artists tested commercials for Disturbing Behavior, an R-rated horror thriller, before more than 400 12- to 20-year-olds. A survey reported that they felt the "standout scene" was one of a girl bashing her head into a mirror.
Columbia Tristar's researchers interviewed 50 children ages 9 to 11 to evaluate concepts for the sequel to the slasher film I Know What You Did Last Summer.
"There is evidence to indicate that attendance in the original movie dipped down to the age of 10," explained a memorandum from the National Research Group, the studios' top market research organization. "Therefore, it seems to make sense to interview 10- to 11-year-olds."
These incidents and others are recorded in confidential marketing documents submitted by nine movie studios to the Federal Trade Commission, which investigated the marketing of violent entertainment to children.
The documents show that some of the biggest companies in Hollywood routinely recruited teenagers and children as young as 9 to evaluate story concepts, commercials, theatrical trailers and rough cuts for R-rated movies.
In some of the memorandums describing marketing strategy, movie studios and video-game makers acknowledged that although they have publicly identified 18- to 34-year-olds as their primary audience for restricted movies and games, they needed the support of young teenagers. Young people make up a disproportionate amount of overall movie ticket-buyers.
On Tuesday, the movie industry's trade association, the Motion Picture Association of America, announced steps to restrict its marketing of R-rated films to underage children. Among them is a pledge not to use children younger than 17 in test screenings unless they are accompanied by an adult.
Jack Valenti, the association's chairman, said the FTC's report had prompted studios to take "a fresh new look at the way we market films."
The industry's program is the latest consequence of the FTC's sharply critical report on marketing practices in the movie, music and video-game industries. Citing regulations prohibiting it from releasing trade secrets, the report did not reveal the names of the entertainment companies involved or the details of the marketing campaigns.
But those details are in the report's documents, which were obtained by The New York Times.
Eight movie studio executives are scheduled to testify Wednesday before the Senate Commerce Committee about their policies.
When asked about the confidential reports Tuesday, Mr. Valenti said, "I didn't know it was happening." He said the "practice of going to 10- and 12-year-olds is really not acceptable."
Joseph Farrell, co-chairman of the National Research Group, said that information for marketing is gathered in many ways, including telephone surveys and test screenings of movies, commercials and theatrical trailers.
"All of the specifications that we carry out, including the methodology involving focus groups, are prescribed by the studios," said Mr. Farrell, who noted that no one younger than 12 is involved without parents' permission.
For test screenings, younger people are accompanied by parents, Mr. Farrell said. He described the process of gathering information from focus groups of younger children as unusual.
Disney announced this month that it would not show R-rated films to focus groups with participants younger than 17 and would urge theaters to more strictly enforce age restrictions.
But marketing plans from the company's units, Touchstone and Hollywood Pictures, show that the studio has turned to younger children for market research on R-rated films, including Judge Dredd.
The Nickelodeon link
Marketing plans for other films show meticulous efforts of major movie studios to gauge the tastes of younger, often underage moviegoers.
In 1997, for example, Columbia was aggressively targeting a young audience for the futuristic science-fiction thriller The Fifth Element.
The studio sought to advertise the movie on the children's network Nickelodeon. MTV Networks, which oversees Nickelodeon, refused to allow an advertisement because it considered the movie inappropriate for its viewers, most of whom are younger than 12.
The studio then unsuccessfully appealed the ban, arguing in part that the science-fiction genre required a suspension of belief and that the violence would be suspect to "the children of today who are more sophisticated." In addition, they noted, "this film needs the audience that Nickelodeon provides to be successful."