Validation and assessment of the self-injurious behavior scale for tic disorders (SIBS-T)

Self-injurious behavior (SIB) is a well-known phenomenon in patients with chronic tic disorders (CTD). To investigate prospectively symptomatology of SIB in adults with CTD, we developed and validated the self-injurious behavior scale for tic disorders (SIBS-T). Patients completed the SIBS-T and a variety of assessments for tics and comorbidities. We investigated SIB frequency, internal consistency of the SIBS-T, and carried out an exploratory factor analysis (EFA). We enrolled n = 123 adult patients with CTD. SIB was reported by n = 103 patients (83.7%). The most frequently reported SIB were beating/pushing/throwing and were found in 79.6% of cases. Patients with SIB had significantly higher tic severity measured with the Adult Tic Questionnaire (ATQ) ( p = 0.002) as well as higher severity of psychiatric comorbidities such as obsessive–compulsive symptoms (OCS) ( p < 0.001,), attention deficit/hyperactivity disorder (ADHD) ( p < 0.001,), and anxiety ( p = 0.001). In addition, patients with SIB had significantly lower quality of life ( p = 0.002). Pearson correlations demonstrated significant associations between SIB and severity of tics ( p < 0.001), depression ( p = 0.005), ADHD ( p = 0.008), and borderline personality traits ( p = 0.014). Consequently, higher SIBS-T also correlated with greater impairment of quality of life ( p < 0.001). The internal consistency of the SIBS-T was good (α = 0.88). The EFA confirmed a single factor underlying the SIBS-T.