Trigger warnings—notes of caution that inform students they are about to consume potentially traumatic course material—have "trivial effects" on mental health, according to a new study that casts significant doubt on whether the controversial classroom tool should be used.

The study, which recently appeared in Clinical Psychological Science, pushes back against the findings of Harvard University researchers, who suggested that trigger warnings might actually be a net negative—they could make some people less resilient to trauma. Trigger warnings don't really leave anyone worse off, according to the newer research conducted by a team of researchers from the University of Waikoto and the City University of New York. But they don't help matters, either: Study participants who received a trigger warning were just as bothered by traumatic words and images as participants who saw the words and images without any forewarning.

"These results suggest a trigger warning is neither meaningfully helpful nor harmful," wrote the authors.

The study involved six experiments and exposure to both disturbing written material and video clips. Researchers also asked participants about their previous experience with traumatic episodes, but determined that trigger warnings were effectively useless, "even for people with a history of trauma."

The study's editor was Scott Lilienfeld, a clinical psychologist at Emory University whose past work on microaggression theory—which he found lacking in scientific rigor—was terrific.

Trigger warnings may still be of use to students who want forewarning of potential traumatic material so that they can skip class altogether. But the authors caution that "college students are increasingly anxious, and widespread adoption of trigger warnings in syllabi may promote this trend, tacitly encouraging students to turn to avoidance, thereby depriving them of opportunities to learn healthier ways to manage potential distress."

At the very least, it would seem that mandatory trigger warnings—a common demand of student activists—are not worth the effort.