Students are requesting and professors issuing trigger warnings —content warnings cautioning that college course material may cause distress. Trigger warnings are meant to alleviate distress students may otherwise experience, but multiple lines of research suggest trigger warnings could either increase or decrease symptoms of distress. We examined how these theories translate to this applied situation. Across six experiments, we gave some college students and Internet users a trigger warning but not others, exposed everyone to one of a variety of negative materials, then measured symptoms of distress. To better estimate trigger warnings’ effects, we conducted mini meta-analyses on our data, revealing trigger warnings had trivial effects—people reported similar levels of negative affect, intrusions, and avoidance regardless of whether they had received a trigger warning. Moreover, these patterns were similar among people with a history of trauma. These results suggest a trigger warning is neither meaningfully helpful nor harmful.

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