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

Abstract

To establish the reliability and validity of verbal fluency testing in patients with multiple sclerosis (MS). Each patient was assessed twice 7-14 days apart on a test of phonological fluency and again 7-14 days later when half of the patients were assessed for phonological fluency by a second assessor while the other half was assessed by the first assessor using a test of semantic fluency. A specialist young disabled unit. Thirty-five patients with multiple sclerosis. Phonological fluency (PF) was tested giving the patient 60 seconds to generate words starting with 'F' 'A' and 'S'; semantic fluency (SF) with names of animals and fruits. Also used were the Short Orientation-Memory-Concentration Test and the Barthel ADL Index. 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. Phonological fluency testing is reliable in people with MS.