A normative study of lexical verbal fluency in an educationally-diverse elderly population

Psychiatry Investig. 2013 Dec;10(4):346-51. doi: 10.4306/pi.2013.10.4.346. Epub 2013 Dec 16.

Abstract

Objective: Lexical fluency tests are frequently used to assess language and executive function in clinical practice. We investigated the influences of age, gender, and education on lexical verbal fluency in an educationally-diverse, elderly Korean population and provided its' normative information.

Methods: We administered the lexical verbal fluency test (LVFT) to 1676 community-dwelling, cognitively normal subjects aged 60 years or over.

Results: In a stepwise linear regression analysis, education (B=0.40, SE=0.02, standardized B=0.506) and age (B=-0.10, SE=0.01, standardized B=-0.15) had significant effects on LVFT scores (p<0.001), but gender did not (B=0.40, SE=0.02, standardized B=0.506, p>0.05). Education explained 28.5% of the total variance in LVFT scores, which was much larger than the variance explained by age (5.42%). Accordingly, we presented normative data of the LVFT stratified by age (60-69, 70-74, 75-79, and ≥80 years) and education (0-3, 4-6, 7-9, 10-12, and ≥13 years).

Conclusion: The LVFT norms should provide clinically useful data for evaluating elderly people and help improve the interpretation of verbal fluency tasks and allow for greater diagnostic accuracy.

Keywords: Age; Education; Elders; Korean; Lexical verbal fluency; Normative data.