Evidence of validity and reliability of a phonological assessment tool.

PURPOSE

To present evidence of the validity and reliability of a phonological assessment tool developed to assess the phonological inventory of Brazilian Portuguese.

METHODS

The study included 866 children aged between 3 and 8:11 years, divided into three groups: typical, control and clinical. Participants were evaluated using a phonological assessment software, which prompted the spontaneous naming of a series of images. The children's responses were audio recorded and transcribed at the time of the assessment, by the software itself. The Cronbach's alpha coefficient was used to evaluate the internal consistency of the instrument for reliability and validity purposes. Criterion validity was examined by comparing the performance of different groups using Student's t-test for independent samples. Intra- and inter-rater agreement were investigated using Kendall's tau. Results were considered significant at p ≤ 0.05.

RESULTS

The present study provided evidence of validity and reliability (internal consistency) for this phonological assessment tool, confirming the reliability of its items and demonstrating excellent agreement rates between examiners regarding its scoring (intra- and inter-rater reliability). The criterion validity assessment demonstrated that the control group outperformed the clinical group across all phonemes, showing that test scores were successful in identifying children with speech sound disorders (phonological disorders).

CONCLUSION

The present findings provide strong evidence of the validity and reliability of this phonological assessment tool.