Researchers examined the number of suicides in children aged 10 to 17-years-old, from January 2013 to December 2017.
The show was released in March 2017.
In April 2017 the suicide rate was 0.57 per 100,000 people, which was nearly 30 per cent higher than in the preceding five years examined in the study.
Additional analysis found that the April rate was also higher than in the previous 19 years.
There were also 195 more suicides than would have been expected in the nine months following the show’s release, the study’s authors estimated.
“Contrary to expectations, these associations were restricted to boys,” they said.
“Among 18- to 29-year-olds and 30- to 64-year-olds, we found no significant change in level or trend of suicide after the show’s release, both overall and by sex.”
The authors added that the show’s release had no impact on the rate of murders.
Their report is published in the Journal of Child and Adolescent Psychiatry.
The study cannot prove that the show was the cause for the rise in suicides.
Its authors acknowledge that they were unable to account for other factors that might have played a part in some deaths.
But Jeff Bridge, the study’s lead author, criticised the depiction of suicide in 13 Reasons Why.
“The creators of the series intentionally portrayed the suicide of the main character. It was a very graphic depiction of the suicide death,” he said.
He added that such portrayals can trigger suicidal behaviour.
Experts have noted a rise in suicide rates among US adolescents across recent years.
Lisa Horowitz, the study’s co-author, called the issue “a major public health crisis”.
Critics of 13 Reasons Why have also warned previously about the show’s portrayal of suicide.
Netflix has included warning messages for some of its episodes and created a website for those in crisis.
“We’ve just seen the study and are looking into the research,” a spokesperson for the streaming company said.
He added that a University of Pennsylvania study published last week found fewer suicidal thoughts among young adults who watched the show than in non-viewers.
“This is a critically important topic and we have worked hard to ensure that we handle this sensitive issue responsibly,” he said.
“Whenever a TV series covers suicide as a topic we always recommend this is dealt with carefully and the production team really pay attention to the sensitivities involved,” Lorna Fraser, who leads the Samaritans’ Media Advisory Service, told The Independent.
“Anyone feeling vulnerable when watching a suicide storyline can find they are susceptible to triggers and this can prove harmful, so it’s vital that these storylines are handled responsibly.”
Additional reporting by agencies
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