Unraveling the heterogeneity of Functional Somatic Symptoms

Functional Somatic Symptoms (FSS) are physical symptoms without an underlying pathology. FSS and patients are heterogeneous, but existing assessment tools for FSS cannot handle this heterogeneity because: 1) The sum scores on the assessment tools do not accurately reflect the severity of FSS, 2) The assessment tools do not distinguish different patterns of reporting FSS. We propose to address these problems by moving to a personalized assessment with Item Response Theory (IRT). IRT provides precise measurements that target which reported symptoms are more reflective of FSS severity, and which are the (a)typical patterns of FSS manifestation. By addressing these issues, we can personalize assessments and offer individual feedback. Moreover, we can identify individual-specific factors, relevant to the etiology of FSS.