Systematic administration and analysis of verbal fluency tasks: Preliminary evidence for reliable exploration of processes underlying task performance

Abstract

Verbal fluency (VF) tasks are typically scored by the total number of acceptable words generated within an allotted time (i.e., total score). VF task total scores can differentiate groups such as healthy subjects and patients, but they do not provide insight into the linguistic and cognitive processes underlying VF performance. To increase the analytical and explanatory power VF tasks can carry, further analysis of errors, temporal parameters, clustering, and switching have been implemented. Systematic scoring guidelines are needed for VF task analysis to be comparable across studies. In this pilot study, we generated detailed instructions for language- specific administration, scoring, and analyses of VF tasks to increase the reliability and validity across studies implementing VF tasks. We demonstrate the analysis for total scores, errors, temporal parameters, task congruent and task discrepant clustering, and switching with strong inter-rater reliability in three phonemic (/k/, / a/, and /p/) and one semantic (animals) category with data of healthy, Finnish speaking adults (N = 50). Our results show that all proposed analyses contribute to VF task performance. We discuss the importance of systematic guidelines and analyses and believe that our analysis on a representative sample of healthy, older monolingual speakers can provide guidance and a starting point for specific VF task performance analyses in various clinical populations.