False Positives for Criterion A Trauma Events and Posttraumatic Stress Disorder Symptoms with Questionnaires Are Common in Children and Adolescents and Could Not be Eliminated with Enhanced Instructions

Objective: Self-report questionnaires are common for measuring posttraumatic stress disorder (PTSD). The experience of life threat-Criterion A-serves a gatekeeper function for diagnosing PTSD, and evidence suggests false positives are common on questionnaires. It remains unknown how common they are and whether extra instructions can reduce them. Methods: The present study assessed 42 youths, 10-17 years of age, from a clinic setting. Youths and parents completed regular PTSD questionnaires and then enhanced versions with more detailed instructions and examples of Criterion A and non-Criterion A events. Parents completed a semistructured interview as the verification of true versus false positives. Results: In the full sample, parents endorsed 41 and children endorsed 45 false positive events. The mean was significantly greater than zero for both parents and children. Parents endorsed 59 and children endorsed 138 false positive symptoms. When false positive events were endorsed, this was significantly associated with more false positive symptoms for both parents and children. An enhanced questionnaire failed to reduce false positive events for the full sample. Discussion: The common occurrence of false positives suggests caution is warranted when interpreting estimates from questionnaire-based research about the prevalence of PTSD. While this attempt to eliminate false positives was not fully successful, there may be other useful enhancements to consider in future research.