Forensic study on the effect of age and illness (Parkinsonism) on handwriting characteristics

Abstract

Background: Handwriting is a neuromuscular task. Old age and illness may produce significant deteriorating effects on the quality of handwriting/signatures of an individual. In some cases, the affected writings may be suspected of being forged due to poor line quality of handwriting. Important documents such as wills, receipts, agreements, contracts, notes, and drafts involve handwritten contents that are often questioned to prove their identity and genuineness. The document examiners may face difficulty to get an adequate number of contemporary standard samples while handling questioned handwriting samples of old age persons and Parkinsonism patients. Therefore, we conducted a qualitative and statistical study to analyze the changes in various handwriting features due to old age and Parkinsonism. Methodology: Handwriting samples from 50 healthy old age persons and 25 individuals suffering from Parkinsonism were collected with their consent. Handwriting features such as line quality defects (tremors, retouchings, and pen lifts), letter formations, abbreviation/simplification of letters or their parts, nature of initial and terminal strokes, nature of connecting strokes, writing speed, overall size, and alignment were analyzed qualitatively and statistically through paired t test using SPSS software. Results: According to results, marked variations were evident in most of the handwriting features in case of old age persons and in case of individuals suffering from Parkinsonism. Two features, namely retouchings and alignment, were least affected in the handwritings of patients suffering from Parkinsonism. Conclusion: According to the results of this study, old age and illness affect the handwriting of an individual in a considerable manner. Marked deterioration in the quality of handwriting/signatures can be observed in case of old age persons and in individuals suffering from Parkinsonism, which makes their writing appear different altogether as compared to their corresponding normal writing. The document examiner must be aware of this fact while examining such cases.