Impact of Demographic and Deployment Related Factors on Structured Inventory of Malingered Symptomatology Performance in Veterans and Service Members.

Background: Screening for feigning and exaggeration in military populations is necessary for accurate interpretation of findings in clinical and research settings. The Structured Inventory of Malingered Symptomatology (SIMS) is a commonly used symptom validity measure, but little is known about the impact of non-clinical factors on its performance. The primary objective of this study was to examine relationships among demographic and deployment-related characteristics and SIMS performance in a cohort of veterans and reservists.

Methods: One hundred and sixty-two participants with a history of combat deployment completed the SIMS and a measure of combat exposure. Demographic and deployment-related information was also collected. Multiple linear regression models were created to determine the impact of demographic and deployment-related factors on the SIMS total score and scale scores.

Results: Higher SIMS total scores were associated with more severe combat exposure, being unemployed, being married or divorced as opposed to being single, and fewer years of education. Higher Neurological Impairment scale scores were associated with being unemployed, being married or divorced, fewer years of education, and older age. Furthermore, higher amnestic disorders scale scores were associated with more severe combat exposure and being unemployed, and higher affective disorders scale scores were associated with more severe combat exposure, fewer years of education, and older age.

Discussion: Notable relationships between SIMS scores and several demographic and deployment-related factors were identified. This was the first study that examined relations of demographic and deployment factors and SIMS performance in a military population.