Dick Uliano, wtop.com

WASHINGTON – Many teenagers keep their cellphones near their beds at night, not just for the alarm clock but so they’ll be accessible if their friends try to reach them.

Texting is the preferred way of communicating.

But Japanese researchers, writing in the Journal of Pediatric Psychology, say they’ve uncovered a risk.

They say they’ve found links between adolescents who use their phones after going to bed and poor mental health, suicidal thoughts and self-injury compared to adolescents who didn’t use their phones late at night.

The researchers say their study ruled out other factors including alcohol and drug use as possible causes of the increased risk.

The study analyzed completed questionnaires by nearly 18,000 adolescents in grades 7-12.

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