In an interview, Mr. Dana said he had reached many of the same conclusions as the Columbia report in his own efforts to examine the article, but he disagreed with the report’s assertion that the magazine had staked its reputation on the word of one source. “I think if you take a step back, our reputation rests on a lot more than this one story,” he said.

Ms. Erdely first heard Jackie’s account in a phone conversation last July, the report said. Jackie told her she had been lured to a darkened room at a fraternity party in September 2012, and raped by seven men, the article said, led by her date for the evening, a lifeguard at the university’s aquatic center identified only as Drew. Ms. Erdely hung up the phone “sickened and shaken,” the report said.

Despite some misgivings about the vividness of some of the details, which included a smashed glass coffee table and an assault with a beer bottle in the published account, Ms. Erdely interviewed Jackie seven more times between July and October of last year.

The first misstep during the reporting process, the Columbia report said, was that Ms. Erdely did not seek to independently contact three of Jackie’s friends, who were quoted in the piece, using pseudonyms, expressing trepidation at the idea of Jackie telling the authorities that she had been assaulted. The quotes came from Jackie’s recollection of the conversation. Those friends later cast doubt on Jackie’s story in interviews with The Washington Post and denied saying the words Rolling Stone had attributed to them. The three told the report’s authors that they would have made the same denials to Rolling Stone if they had been contacted.

Rolling Stone, the report said, also did not provide the fraternity with enough information to adequately respond to questions from the magazine. Later, when the article had been published, the fraternity, Phi Kappa Psi, said it did not host a function on the weekend Jackie had specified.

And the magazine failed to identify Jackie’s attacker, the report said. It was content to give him a pseudonym, Drew, when Jackie resisted Ms. Erdely’s request to help find him. The fraternity, The Post and the police have been unable to find anyone who matches Jackie’s description of Drew.