Verbal fluency assessment of patients with multiple sclerosis: test–retest and inter-observer reliability

Abstract

Objective: To establish the reliability and validity of verbal ‘uency testing in patients with multiple sclerosis (MS).

Design: Each patient was assessed twice 7–14 days apart on a test of phonological ‘uency and again 7–14 days later when half of the patients were assessed for phonological ‘uency by a second assessor while the other half was assessed by the first assessor using a test of semantic ‘uency.

Setting: A specialist young disabled unit.

Subjects: Thirty-five patients with multiple sclerosis.

Measures: Phonological ‘uency (PF) was tested giving the patient 60 seconds to generate words starting with ‘F’ ‘A’ and ‘S’; semantic ‘uency (SF) with names of animals and fruits. Also used were the Short Orientation–Memory–Concentration Test and the Barthel ADL Index.

Results: On the first occasion 31/35 patients could be tested, and the average (SD) score of the PF was 21.9 (12.1), median 18. The test–retest reliability (n = 30/35) of the PF was good (Pearson r = 0.85). The score difference between the first two occasions ranged from +17 to –15 (median –3, mean –2.9, SD 6.7). The inter-observer reliability (n = 13/16) of the PF was good (Pearson r = 0.90). The difference of the score between the two assessors ranged from –9 to +6 (median 0, mean –1.2, SD 4.9). The correlation (Pearson) of the PF score with the SF, Barthel and SOMC was respectively r = 0.59, r = 0.27 and r = 0.63.

Conclusions: Phonological ‘uency testing is reliable in people with MS.