Swedish normative data and longitudinal effects of aging for older adults: The Boston Naming Test 30-item and a short version of the Token Test

Abstract

Naming ability and verbal comprehension are cognitive functions that may be affected both by normal aging and by disease. Neuropsychological testing is crucial to evaluate changes in language ability and reliable normative data for all ages are needed. We present clinically useful test norms, together with subsample analysis of longitudinal effects of aging, for two robust and well-known tests that evaluate naming ability and verbal comprehension where the present norms for older adults (aged 85 and older) are sparse or missing. Participants (n = 338) from a Swedish population-based study, the Elderly in Linköping Screening Assessment, were cognitively evaluated with a cognitive screening battery at the age of 85 years and followed to the age of 93 years. Normative data at age 85 years were calculated from a sample (n = 207) that was determined as cognitively healthy after application of rigorous exclusion criteria. Effects of normal aging were investigated by analyzing follow-up performance at age 90 and 93 years for the subsample of cognitively healthy that completed the entire study. The evaluated tests in this study are Swedish versions of the Boston Naming Test 30-item Odd Version (BNT-30) and a short form of the Token Test, Part V (TokV). Analyzes of effects of aging showed that performance decreased with age for BNT-30, but not for TokV. Higher education was associated with better performance in both tests and men performed better than women on the BNT-30. Results also showed naming ability to be more sensitive to aging than verbal comprehension.