NYU has retracted a survey of MTA subway and bus workers that found 89% of respondents claimed to have been assaulted or harassed on the job.

In a letter to the MTA on Friday, the lead researcher Robyn Gershon said her team had “detected anomalies” in the data it used for the study, which was published in August. The survey was supposed to have been emailed only to transit workers, but NYU discovered it had been posted on a public Facebook group.

“In light of this, we have concluded that the database was likely contaminated and that the veracity of the data … is not verifiable,” Gershon wrote.

When the study came out, the MTA disputed the findings, claiming a survey of 1,297 transit workers was not representative of the more than 50,000 transit workers employed by the agency.

NYU dean and professor of biostatistics Melody Goodman said the university was “taking corrective measures” in a letter to New York City Transit President Demetrius Crichlow.

Crichlow had previously accused NYU of trying to “stir panic” among transit workers and said the survey used “flawed methodology.”

“These incidents do not occur anywhere near as frequently as the report suggests,” he wrote.