Background and objectives: Students with high levels of test anxiety frequently experience depersonalization during examinations. We investigated whether a brief cognitive behavioral group intervention reduces these symptoms.

Design: Randomized controlled trial.

Methods: Students with high levels of trait test anxiety and impairing depersonalization symptoms during their last oral examination were randomized. While the intervention group (n = 22) received a group training, a control group (n = 16) underwent an active waiting time protocol. Effects of the intervention on depersonalization severity and its appraisal, attention focus, emotion regulation, anxiety, heart rate, and heart rate variability within the Trier Social Stress Test for groups were examined. A follow-up assessment was conducted after a university oral examination. Registration number: DRKS00010190.

Results: Depersonalization and its appraisal significantly changed within the intervention group, but not within the control group. The intervention group reported significantly less self-focused attention and fear and used the coping strategy reappraisal significantly more often. No significant Group × Time interaction was detected regarding heart rate and heart rate variability. Follow-up results give a first indication of the reduction of depersonalization through the intervention in a naturalistic setting.

Conclusion: The intervention seems promising for treating depersonalization in students with high levels of trait test anxiety.