Psychometric validation of the 16 Item Quick Inventory of Depressive Symptomatology Self-Report Version (QIDS-SR₁₆) in military veterans with PTSD

Background The Quick Inventory of Depressive Symptomatology-Self Report (QIDS-SR₁₆) is one example of a screening tool for depression, which has been utilized extensively following validation in a number of clinical populations. Despite the strengths of the QIDS-SR₁₆, it has not been validated in military veterans, a particularly unique population considering their exposure to trauma and high rate of psychiatric comorbidities. The current report describes a psychometric validation of the QIDS-SR₁₆ in a sample of United States military veterans diagnosed with military-related PTSD. Methods Participants (n=240) were administered the QIDS-SR₁₆ and one of two gold-standard semi-structured interviews to establish diagnosis of a current Major Depressive Episode (MDE). The ability to discriminate between individuals with and without a current MDE using the QIDS-SR₁₆ was tested with a stepwise logistic regression. Additionally, an optimal cutoff score for the QIDS-SR₁₆ was established. Results The QIDS-SR₁₆ was able to reliabily discriminate between individuals with and without a current MDE. The optimal cutoff score of the QIDS-SR₁₆ for a current MDE was 13, with a sensitivity of 77.55% and specificity of 56.25%. Limitations Limitations of this study included underrepresentation of some racial/ethnic groups, the inability to disentangle the potential influence of trauma type and gender on results, and the use of two diagnostic interviews to diagnose current MDE. Discussion The QIDS-SR₁₆ can be effectively utilized in military veterans with comorbid PTSD. However, the calculated cutoff score for this population was higher than the cutoff score for the general population. This could result from the overlap between PTSD and MDE symptoms.