Clinical checks lower PTSD classifications in 5,070-adult European survey

Adding brief clinical checks to the International Trauma Questionnaire substantially lowered the proportion of adults classified as having post-traumatic stress disorder or complex post-traumatic stress disorder in a survey of 5,070 adults across five European countries. The study found that 19.2% of participants met diagnostic requirements using the standard ITQ, compared with 9.8% when the checks were included.

Researchers used quota-based sampling to recruit adults in the Czech Republic, Poland, Hungary, Romania and Slovakia. Most respondents, 82.2%, were trauma-exposed. Under the standard questionnaire, 7.2% met diagnostic requirements for PTSD and 12.0% met the requirements for complex PTSD. With clinical checks, the corresponding proportions were 3.9% and 5.9%. These figures represent changes in diagnostic classifications, not verified counts of false diagnoses.

The clinical checks are brief follow-up questions intended to verify that respondents understood the ITQ symptom items. The checked version produced scores with excellent factorial validity and internal reliability. Latent classes continued to correspond to PTSD and complex PTSD, indicating that the additional comprehension step preserved the questionnaire’s ability to organize responses into clinically recognizable symptom patterns while identifying fewer cases.

The checked ITQ also showed stronger associations than the standard version with suicidality and concurrent anxiety-depression symptoms. Participants were more likely to retain their diagnostic status when clinical checks were used if they were female, had more extensive trauma histories or reported higher levels of anxiety-depression symptoms. The investigators described the resulting prevalence estimates as more plausible than those generated by the standard ITQ and concluded that the checks added clinically relevant information to symptom assessment. However, the evidence comes from a five-country European survey using self-report data, and the results do not establish whether the lower classifications were incorrect or whether the approach improves clinical outcomes.

Subject of Research: Psychometric performance and diagnostic classification of the International Trauma Questionnaire with clinical checks in five European countries

Article Title: Examining the performance of the International Trauma Questionnaire with clinical checks in a multinational European sample

Article References: Hyland, P., Shevlin, M., Ben-Ezra, M., Cloitre, M., Adamkovic, M., Błachnio, A., Preiss, M., Salgo, E., Stanculete, M. F., Unoka, Z. S., & Karatzias, T. (2026). Examining the performance of the International Trauma Questionnaire with clinical checks in a multinational European sample. PLOS One, 21(10), e0360940. https://doi.org/10.1371/journal.pone.0360940

Image Credits: AI Generated

DOI: 10.1371/journal.pone.0360940

Keywords: International Trauma Questionnaire, PTSD, complex PTSD, clinical checks, psychometrics, self-report, European survey, suicidality, anxiety-depression, Examining, performance, International