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

ABSTRACT

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.

KEYWORDS:

• Forensic neuropsychology
• testamentary capacity
• dementia
• normative data
• neurodegenerative disease

Acknowledgment

The Authors are grateful to participants who took part in the present study. The Authors would like to thank Prof. Erminio Capitani for his essential support in implementing statistical analyses, as well as Dr. Maria Cristina Saetti and Prof. Marcello Gallucci for their insightful advice with regard to methodological and statistical aspects.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Consent to participate

The participant was made fully aware of the aims of the research and written informed consent was obtained.

Data sharing

The data and materials for this study are available at: https://osf.io/8kfnm.

Ethical approval

The study was approved by the Ethics Committees of the University of Milano Bicocca and of the IRCCS Istituto Auxologico Italiano.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/24732850.2024.2359696.

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This research was funded by the University of Milano-Bicocca (grant number ‘2018-ATE-0317’) and by the Italian Ministry of Health to N.B.