German version of the Northoff scale for subjective experience in catatonia (NSSC-dv) : A validated instrument for examination of the subjective experience in catatonia

Abstract

Patients with catatonia often show serious motor, affective and behavioral symptoms, behind which the subjective experience often remains hidden. Therefore, this study disseminates our own systematic empirical investigation of the subjective experience of catatonia patients to aGerman-speaking audience of clinicians and researchers. Based on current evidence and the clinical experience of the authors, the self-report questionnaire Northoff Scale for Subjective Experience in Catatonia (NSSC) was modified, extended and validated and now consists of 26items capturing the subjective experience of catatonia in its clinical diversity. A total of 46patients with catatonia according to the International Classification of Diseases(11th revision, ICD-11) were asked about their subjective experience during the acute phase of the disease using the NSSC. The NSSC showed high internal consistency (Cronbach's alpha = 0.91). The NSSC total score was significantly associated with the Northoff Catatonia Rating Scale (NCRS; r = 0.46; p < 0.05), the total score of the Positive and Negative Syndrome Scale (PANSS; r = 0.30; p < 0.05), the Brief Psychiatric Rating Scale (BPRS; r = 0.33; p < 0.05), and Trait Anxiety (STAI; r = 0.64; p < 0.01), supporting its validity. Preliminary validation of the NSSC revealed good psychometric properties. The NSSC is auseful instrument for routine clinical use to assess the subjective experience of patients with catatonia in order to provide tailored psychotherapeutic interventions.