The Testament Definition Scale (TDS): Normative Data from the Italian Population and Clinical Usability in Neurodegenerative Diseases

Ad-hoc forensic instruments have been developed for the contemporaneous or retrospective evaluation of testamentary capacity, among which the Testament Definition Scale (TDS), a short rating scale designed to evaluate and quantify the individual’s capacity to give an exhaustive definition of what a testament is. The aim of the study was to derive Italian normative values for the TDS in an adult sample and to provide preliminary evidence for its usability in neurological patients with cognitive decline. The TDS was administered to 341 healthy subjects of different ages (range= 30–92 years) and educational levels (range= 1–20 years), along with the Montreal Cognitive Assessment (MoCA) and the Frontal Assessment Battery (FAB), and to 6 adults with neurodegenerative diseases. In healthy subjects, TDS scores were associated with MoCA and FAB scores;; education was the only significant predictor of TDS scores. In patients with neurodegenerative diseases, TDS scores can dissociate from MoCA and FAB scores. Normative data (cutoff and equivalent scores) for favoring the adoption of the TDS in the assessment of testamentary capacity are here provided.