Aim: To determine the relationship between performance on the Digital Trail Making Peg test (DTMP) and cognitive function in older adults.
Methods: A total of 203 community-dwelling older adults (mean age: 76.4±5.1 years old) participated in this study. The five-cog test was used to assess the cognitive function. The DTMP measured completion time, number of errors and intra-individual variability for performance variability (coefficient of variation, CV; inter-elemental variability, IEV). Spearman's rank correlation coefficient (ρ) was calculated to examine the association between each variable. In addition, a multiple regression analysis was performed with the cognitive function score as the dependent variable and the DTMP completion time, number of errors, CV, and IEV as the independent variables, with adjusting for the sex, age, years of education, body mass index, medical history, depression, and physical function.
Results: The rank correlation coefficients with cognitive function scores were as follows: completion time, ρ = -0.479 (P < 0.01), number of errors, ρ = -0.068 (P = 0.332), CV, ρ = 0.085 (P = 0.225), IEV, ρ = -0.316 (P < 0.01). The results of the multiple regression analysis showed that completion time (β = -0.566), CV (β = 0.164), IEV (β = 2.736) were significantly associated with cognitive function scores.
Conclusions: The shorter the DTMP completion time, the better the overall cognitive function. However, the intra-individual variability of CV and IEV did not show consistent results, with smaller values indicating less intra-individual variability.
Keywords: Attentional function; Coefficient of variation; Dual task; Hand dexterity; Inter-element variability.