“Symbol Digit Modalities Test” normative values for Spanish home care residents: a pilot study

Abstract

Introduction. The Symbol Digit Modalities Test (SDMT) is a widely used test for the evaluation of neurological disorders. Normative data have been published for this test in different populations, however there are no values regarding elderly persons residing in geriatric homes. This study has aimed to apply the SDMT on a sample made up of Spanish elderly people living in geriatrics home care residents to obtain normative values, considering gender, age and education level.

Methodology. The standard pen and paper version of the SDMT was administered to 821 home care residents older than 55 years. Information regarding age, gender and education was obtained by means of personal health records provided by each institution. A descriptive analysis was made to generate tables including normative data. The final values were adjusted based on age and educational level of the participants and presented in weighted scales.

Results. The SDMT was filled out by 321 participants. Final distribution of the sample made it possible to calculate normative values based on age. A negative correlation was observed between the SDMT mean score and age of the participants while education significantly affected the results obtained.

Conclusions. The SDMT normative data obtained after the application of the SDMT in the elderly living in home care residents were found to be strongly influenced by age and education. Use of the oral version is recommended for future studies of this kind.