The impact of selecting different contrasts in phonological therapy

Previous research indicates that the extent of progress made by children with phonological disorders depends upon the nature of the word pairs contrasted in therapy. For example, phonemes that differ maximally in terms of place, manner, voicing and sound class (e.g., fan - man) in comparison to therapy where the word pairs presented differ minimally (e.g., fan - van). To investigate the implications of target selection within a typical clinical context (as opposed to a rigorous research setting) eight speech-language pathologists implemented intervention with appropriate children from their caseloads. Nineteen children each received 6 hours of therapy over one school term. They were randomly allocated to two groups. One group (of nine children) received intervention based on a traditional minimal pair approach, targeting homonymy as well as distinctive feature contrast. The other group (ten children) received intervention targeting contrasts differing across a range of distinctive features. Children made considerable progress in therapy in terms of speech accuracy and number of error patterns suppressed. However, there was no difference between the progress of the two groups. Follow-up assessment of 14 of the 19 children indicated maintenance of progress by both groups. Reasons for the lack of difference between the groups in the current study are considered and clinical implications are drawn.