Objective: Sleep disturbances play a fundamental role in the pathophysiology posttraumatic stress disorder (PTSD), and are not only a secondary feature. The aim of this study was to validate and assess the psychometric properties of the Brazilian version of the Pittsburgh Sleep Quality Index Addendum for PTSD (PSQI-A-BR), a self-report instrument designed to assess the frequency of seven disruptive nocturnal behaviors, in a sample of participants with and without PTSD. Methods: PSQI-A was translated into Brazilian Portuguese and applied to a convenience sample of 190 volunteers, with and without PTSD, who had sought treatment for the consequences of a traumatic event. Results: The PSQI-A-BR displayed satisfactory internal consistency (Cronbach's coefficient of 0.83 between all items) and convergent validity with the Clinician Administered PTSD Scale (CAPS), even when excluding sleep-related items (r = 0.52). Test-retest yielded high agreement in the global PSQI-A-BR, with good stability over time (r = 0.88). A global PSQI-A-BR cutoff score of 7 yielded a sensitivity of 79%, specificity of 64%, and a global score of 7 yielded a positive predictive value of 93% for discriminating participants with PTSD from those without PTSD. Conclusion: The PSQI-A-BR is a valid instrument for PTSD assessment, applicable to both clinical and research settings.Universidade Federal de São Paulo (UNIFESP) Department of PsychiatryUniversity of Pittsburgh School of Medicine Department of PsychiatryUniversidade Federal de São Paulo (UNIFESP) Department of PsychobiologyUNIFESP, Department of PsychiatryUNIFESP, Department of PsychobiologySciEL
