STUDY: Trigger Warnings Are Harmful To College Students says the Daily Wire, describing a study whose participants' average age was 37 and which did not measure harm.

You can find the study involved here. A group of Harvard scientists asked 370 people on Mechanical Turk to read some disturbing passages – for example, a graphic murder scene from Crime and Punishment. Half the participants received the following trigger warning before the passage:

TRIGGER WARNING: The passage you are about to read contains disturbing content and may trigger an anxiety response, especially in those who have a history of trauma

Participants were asked to rate their anxiety before and after reading the passages. After they had finished, they were asked to fill out a bunch of questionnaires that measured their opinions about how trauma worked.

The researchers found that people who received the trigger warning were 5% more likely to endorse the idea that they were vulnerable to trauma, and also 5% more likely to endorse the belief that people with trauma could suffer persistent negative effects from that trauma. There were some subgroup and moderation analyses which I ignore for the usual reasons.

What might be some causes for concern with this study?

First, Stuart Ritchie points out that the results are statistically weak. Most of the results have p-values around 0.05, and are not corrected for multiple testing. That means it hasn't been formally proven whether or not the results are random chance. I don't like haggling over whether something is just above or just below a significance threshold. But if you do like that kind of haggling, this study doesn't survive it very well.