A Meta-Analysis of the Efficacy of Trigger Warnings, Content Warnings, and Content Notes

By Victoria Bridgland, Payton Jones & Benjamin Bellet

Preprint published August 2022


A trigger or content warning aims to alert someone that the material they’re about to consume contains potentially distressing themes. Anecdotally, these warnings are thought to help people emotionally prepare or avoid material. However, in recent years, there has been a increase in studies investigating how well trigger warnings actually work.

Bridgland, Jones and Bellet (2022) conducted a meta-analysis of available literature to determine what individual effects look like when combined.

Research and findings

Following a thorough identification and screening process, 12 reports satisfied the author’s eligibility criteria and were included in the meta-analysis. Each of the authors grouped the extracted outcomes into the following four categories:

  1. Response affect: a participant’s affective (or emotional) state after encountering potentially distressing content.
  2. Avoidance: where a participant opts to skip or avoid being exposed to distressing content.
  3. Anticipatory affect: a change in affect (i.e. emotion) after receiving a trigger warning, but before being exposed to potentially distressing content.
  4. Comprehension: a participant’s comprehension of material in an educational context if a trigger warning is present.

Note: Authors also note papers with additional outcomes that may be useful for future investigations but did not warrant a meta-analysis.

Of the 12 individual reports included in the study, 11 concluded that warnings were ineffective. The results suggested that that:

  • Trigger warnings had a trivial effect on response affect, d = 0.02, [-0.05, 0.1].
  • Trigger warnings had a negligible effect on avoidance, d = 0.06, [-0.09, 0.21].
  • Trigger warnings increased anticipatory affect, d = 0.43, [0.09, 0.77].
  • Trigger warnings had a trivial effect on comprehension, d = 0.06, [-0.02, 0.14].

Note: Effect sizes (d) measure the magnitude of an effect. The larger the effect size, the stronger the relationship. Confidence intervals are presented in brackets.


Overall, authors found that trigger warnings had no meaningful effect on response affect or avoidance. Though, warnings did increase the distress before viewing the actual content.

The authors mention that research to date uses single time point designs and that potentially, small effects may accumulate over time – a noted possibility for future research.

Authors surmised that though there is room for further investigation, “Trigger warnings should not be used as a mental health tool”.