Normalization of Rowland Universal Dementia Assessment Scale (RUDAS) in Chilean older people

Rowland Universal Dementia Assessment Scale (RUDAS) is a cognitive screening that evaluates older people with low educational levels. In Chile, there are no normative data to assess this population.

Objective

To obtain normative data on RUDAS in older Chilean people with up to 12 years of schooling, and to determine whether age and schooling years influence a person's performance on RUDAS and on the items that constitute it.

Methods

A group of cognitively healthy people 60 years old or over, with up to 12 schooling years was evaluated (n=135). Multiple regression models were applied to obtain normative data on RUDAS, according to age and schooling years, and to measure the effects of schooling on different items.

Results

Regression analysis showed that none of the items had schooling as a significant predictor, except for the visuoconstruction item. The variables age and schooling explained 12.6% (R^2=0.126) of the RUDAS total score variance. The item visuoconstruction was the most associated with the educational level (OR=1,147).

Conclusion

This study showed that RUDAS is a recommended instrument for evaluating older people with low educational levels. However, more studies are needed to prove the validity of the RUDAS on Chilean older people.

Test Your Memory-Spanish version (TYM-S): a validation study of a self-administered cognitive screening test

OBJECTIVES

To develop the Test Your Memory (TYM)-Spanish version (TYM-S), a self-administered cognitive screening test, in a Chilean older sample and to estimate its psychometric properties and diagnostic accuracy.

METHODS

The TYM was translated into Spanish and adapted for a Chilean population to develop the TYM-S. Measures of global cognitive impairment and executive dysfunction were administered to 30 controls, 30 dementia patients, and 14 subjects with mild cognitive impairment (MCI). All participants' proxies were interviewed with assessments of dementia severity, functionality in daily living activities, and cognitive change. Convergent validity and internal consistency reliability of the TYM-S were estimated. Cut-off points, sensitivity, and specificity were determined to test its diagnostic capacity for dementia or MCI.

RESULTS

Regarding convergent validity, the TYM-S was significantly correlated (p < 0.001) with global cognitive impairment (Mini-Mental State Examination: r = 0.902; Addenbrooke's Cognitive Examination-Revised-Chilean version: r = 0.922; Montreal Cognitive Assessment: r = 0.923), executive dysfunction (Frontal Assessment Battery: r = 0.862), dementia severity (Clinical Dementia Rating: r = -0.757), functional capacity (Technology-Activities of Daily Living Questionnaire: r = -0.864; Pfeffer Functional Activities Questionnaire: r = -0.748; Instrumental Activities of Daily Living: r = 0.769), and cognitive change (Alzheimer's Disease 8-Chilean version: r = -0.700) measures. Regarding reliability, Cronbach's α was 0.776. Optimum cut-off scores of 39 and 44 distinguished dementia cases from controls (93.1% sensitivity, 82.2% specificity) and MCI cases from controls (85.7% sensitivity, 69% specificity), respectively. The extent of assistance required in the TYM-S and cognitive impairment was correlated.

CONCLUSIONS

The TYM-S is a valid and reliable instrument to assess cognitive impairment, showing good psychometric properties and diagnostic capacity to identify cases of dementia in a Spanish-speaking older cohort. Although its need for assistance may be limiting, its ability to quickly assess several cognitive domains supports widespread clinical use.