Undetected post-traumatic stress disorder in secondary-care mental health services: systematic review

Identification of comorbid post-traumatic stress disorder (PTSD) in patients with other serious mental illness is of substantial importance given that this is associated with poorer clinical outcomes of these disorders,1–4 and that PTSD is a treatable disorder.5 Some studies suggest that a large proportion of patients in secondary-care mental health services with other (non-PTSD) primary diagnoses meet criteria for PTSD on screening, and that there is usually no record of PTSD in the patient’s clinical records.6–9 If these estimates of undetected PTSD are accurate this raises a serious concern that PTSD is not adequately identified through routine clinical care pathways. Other studies, however, report much lower frequencies of undetected PTSD.10–12 Reasons for variation in estimates of PTSD across studies could include differences in the characteristics of the people in the study (such as gender, primary diagnosis) or of the study methodology (such as measurement or selection bias). An accurate estimate of the frequency of undetected PTSD in secondary care, and an understanding of factors associated with variation in frequency is required to determine if, and how, services should respond. In this study, we systematically review the literature to determine whether undetected PTSD is present at a prevalence that would reflect substantial clinical importance within secondary-care mental health services. For the purpose of this study we define ‘substantial clinical importance’ as presence of undetected PTSD in 10% or more of patients in secondary care, an arbitrary value but one that we believe most service providers would agree merits clinical concern. Furthermore, we also aim to determine the extent to which variation in reported estimates might be because of sample characteristics or methodological biases. To our knowledge there have not been any previous systematic reviews addressing these aims.