Supplementary Material for: The German Translation and Validation of the Scale for the Assessment of Thought, Language and Communication: A Factor Analytic Study

The Scale for the Assessment of Thought, Language and Communication (TLC) represents an instrument for the assessment of formal thought disorder (FTD). The factorial dimensionality of the TLC has yielded ambiguous results for a distinction between positive (e.g. circumstantiality) and negative (e.g. poverty of speech) FTD. The purpose of the current study was to first translate and validate the TLC scale in German. Second, the internal structure was explored in order to identify different FTD dimensions. Two hundred and ten participants (146 patients with ICD-10 diagnoses: depression n = 63, schizophrenia n = 63, mania n = 20; 64 healthy subjects) were interviewed and FTD was rated with the TLC. The principal component analysis of the German TLC version revealed a 3-factor solution, reflecting a disorganized factor, an emptiness factor and a linguistic control factor. The current investigation yielded similar results to those originally reported for the TLC. Thus, a distinction between a positive disorganized, a negative and a semantic word level factor can be supported for the German translation.