Eight psychiatric studies were quietly shut down at New York University’s medical school after investigators discovered a series of violations, including falsified records. A top researcher was also dismissed.

According to the New York Times, violations included lax oversight of study participants and failure to keep accurate case histories.

The violations “jeopardize subject safety and welfare, and raise concerns about the validity and integrity of the data collected at your site,” the Food and Drug Administration (FDA) said in a letter, obtained by The Times, to Dr. Alexander Neumeister, the studies’ lead investigator.

Neumeister was put on leave after complaints about the lab’s compliance with research standards were confirmed. He later resigned.

One of the studies included individuals who had a diagnosis of post-traumatic stress disorder caused by childhood abuse. Participants took a relatively untested drug intended to mimic the effects of marijuana so researchers could observe if their symptoms improved, The Times reported.

Individuals with mental disorders are more suseptible to adverse reactions, experts told The Times.

“These are people who are more vulnerable to being exploited in the research process, and more vulnerable to things going wrong during the research, so you want extra vigilance,” Elisa Hurley, the executive director of Public Responsibility in Medicine and Research, a national nonprofit devoted to promoting high research standards, told The Times. “If someone in my family were in a situation like this, I would want to be sure that the institution was crossing its t’s and dotting its i’s.”

According to the FDA investigation, the research team failed to assess at least three of the 50 subjects 24 hours after they were administered the experimental drug, failing study protocol. Neumeister falsified documents by signing another investigator’s name on reports and at least one study participant was part of another trial 16 days earlier, violating the 30-day window required by protocol.

Study participant Diane Ruffcorn, 40, said she was sexually abused as a child. For the study, she was given the drug and the tests, but researchers failed to follow up with her. To prepare for the study, she told The Times, she had to stop taking all of her medications, but the study’s false starts forced her to repeatedly stop and restart her medicatons.

“It was horrible,” Ruffcorn told The Times. “I had flashbacks, returning nightmares, every symptom coming on full force, not to mention the withdrawal. After going off and back on four or five times, I told them, ‘I can’t do this anymore.’”

Ruffcorn, who lives in Seattle, was flown to New York to enter the trial. After the trial period, she said she experienced odd symptoms but was unable to find out whether they were related to the drug because the study was halted and the data belonged to Pfizer, the drug manufacturer. In June, she learned she’d taken the placebo.

According to both NYU and Neumeister’s lawyer, there is no evidence any study participant had been harmed, The Times reported.

The news comes at critical time in two controversial areas of psychiatry research, The Times reported: the search for a blood test or biological sign of post-traumatic stress disorder and use of recreational drugs to treat the diagnosis.

In January, one man died and five others were hospitalized in France during an experimental drug trial for a painkiller. The drug in question had similar marijuana-like effects.

NYU has deemed all study data unreliable and followed up with study participants to monitor their health, The Times reported.