A new study from the University of Michigan has found that the controversial Netflix show 13 Reasons Why may have increased the risk of teen suicide.

The research, published in the journal Psychiatric Services, surveyed 87 teenagers who were being treated in psychiatric emergency departments for suicide-related concerns in 2017 and 2018.

The teenagers, the majority female, were asked to complete a questionnaire during their emergency department visit.

Nearly half (49%) of the teenagers had watched at least one episode of the first season of 13 Reasons Why, and 84% of those had watched it alone.

Over half of the viewers believed that watching the show had increased their risk of suicide due to their identification with the lead female character, Hannah Baker, who kills herself at the beginning of the series after recording tapes detailing the reasons for her decision and the characters who she blames.

Teenagers with more depressive symptoms and suicidal ideation were more likely to report that they identified with Hannah and reported negative emotions while viewing the show.

The authors concluded that while further research is needed to assess the dangers of the show, “the findings suggest a particular vulnerability to the show’s themes among youths at risk of suicide,” and that steps are needed to be taken to ameliorate those problems.

Lead author of the study, Dr Victor Hong, told BuzzFeed News that the researchers decided to undertake the study after noticing a “significant uptick in terms of the volume of teens coming in with suicidal issues” who mentioned the show as an influencing factor.

“Some of them had even said that it was a real factor in why their suicidality or depression had worsened,” said Hong.