Do Patients Underestimate Their Symptoms in Hindsight? An Ambulatory Assessment Study on the Frequency of Dissociation in Posttraumatic Stress Disorder

Abstract

Assessing symptom frequencies is a core feature of psychological diagnostics and any evaluation of the effectiveness of a therapeutic approach is based on these. However, heuristic strategies are employed when estimating the frequency of past events, which can lead to recall biases. While the few studies published to date indicate that patients suffering from posttraumatic stress disorder tend to underreport dissociative symptoms, there is also some evidence for the tendency to overreport dissociative symptoms. To gain insights into absolute frequencies of dissociative symptoms and retrospective reporting styles we used ambulatory assessment in 42 participants with PTSD symptoms. Participants logged their symptoms via smartphone over 2 weeks and then estimated them again retrospectively for this entire period. In comparison to the daily logs, more participants tended to retrospectively underestimate experienced symptoms in their frequency for almost all items. The results reported in this sample thus argue for an underreporting style instead of overreporting of dissociative symptoms.