Abstract
Performance in standard and alternative versions of verbal fluency task was compared during test re-test administration within one week, to measure the practice effect and also validity of the alternative version of the test. Methodology: 20 healthy volunteers (10 men, 10 women), age 25.1 +- 2 years, duration of education 16.7 +- 2.6 years, were assessed by a verbal fluency test with the letters N, K, P and V, R, S.
Results: The NKP version of verbal fluency test significantly correlated with the alternative VRS version in the first and second session (R = 0.63, p < 0.005, R = 0.83, p < 0.001, respectively). Mean total NKP score was significantly higher than mean total VRS score in both sessions (Wilcoxon matched pair test, T = 36, Z = 2.37, p < 0.05, resp.
T = 19.5, Z = 3.19, p < 0.005 respectively). During the second administration after one week, there was a significant increase in performance by 7 and 6 words (improvement by 13%) in NKP and VRS versions (Wilcoxon matched pair test T = 12.5, Z = 3.31, p < 0.001, resp.
T = 15, Z = 3.07, p < 0.005 respectively). Conclusion: The VRS version appeared significantly more difficult than NKP version, so it is not suitable as an alternative for re-testing.
The observed practice effect could however be valid only for the studied population.