Measuring the verbal effectiveness of people with aphasia

A well-known test for measuring verbal functional communication in people with mild expressive aphasia is the Amsterdam-Nijmegen Everyday Language Test (ANELT; Blomert, Koster & Kean, 1995). Previous research has indicated that the construct validity of the ANELT can be further improved by substituting the (original) qualitative scoring procedure by a (new) quantitative one, which takes the number of essential information units. In comparison to the qualitative score, the quantitative score was found to be more sensitive to detect change in functional communication over time and it also allowed derivation of score of verbal efficiency, which is another aspect of functional communication (Ruiter, Kolk, Rietveld, Dijkstra & Lotgering, 2011).
As a follow-up on the study by Ruiter et al. the following further (experimental) adaptations to the ANELT were made: (a) some of the test items were replaced by ones which better represent daily communication settings, and (b) the essential information units to be expressed on each test item were determined on a larger group of non-aphasic speakers than was done in the 2011-study, thus including more (i.e. various) responses.
The current study seeks to investigate whether these experimental changes further improve the methodological quality of the quantitative ANELT measure.

Based on the results obtained in our previous study (Ruiter, Kolk, Rietveld, Dijkstra & Lotgering, 2011), we hypothesise that:

- The experimental changes to the scenarios and new quantitative scoring procedure of the Amsterdam-Nijmegen Everyday Language Test (ANELT; Blomert, Koster & Kean, 1995) lead to a more accurate estimate of the true scores of the verbal functional communication skills of people with mild expressive aphasia. More specifically, by reducing the SDs (SDs < 15.1) the 95% confidence intervals will decrease.

- The new quantitative score is more sensitive than the original qualitative one in detecting change in verbal effectiveness over time. There are two conditions that have to be met in order to investigate responsiveness: the aphasic speakers should improve verbal effectiveness over time (investigated in the current study), and non-linguistically impaired speakers should not (investigated in another study).

- Quantification of the number of essential information units produced in the ANELT yields at least the same inter-rater agreement at the current qualitative rating scale.

Two, with a time interval of 8 weeks

n/a