The integrated use of maximum performance tasks in differential diagnostic evaluations among children with motor speech disorders

TLDR

Maximum performance tasks (MPT) were employed to quantify speech motor capacities in children with spastic dysarthria, developmental apraxia of speech, and normal controls, using vowel and fricative prolongation and syllable repetition rate tests. MPT distinguished spastic dysarthria from developmental apraxia of speech and normal children on monosyllabic repetition rate and vowel prolongation, while developmental apraxia differed from normal on fricative prolongation, trisyllabic repetition rate, sequencing errors, and attempts, underscoring MPT’s value for differential diagnosis.

Abstract

Maximum performance tasks (MPT) were employed to quantify the speech motor capacities of children with dysarthria and developmental apraxia of speech. Specifically, several MPT (i.e. vowel prolongation, fricative prolongation, maximum syllable repetition rate) were conducted among nine carefully selected children with spastic dysarthria, 11 children with developmental apraxia of speech (DAS), and 11 age–matched normal-speaking children. The results indicated that children with spastic dysarthria can be differentiated from both DAS and normal-speaking subjects on only two of the MPT (i.e. monosyllabic repetition rate and vowel prolongation). Children with developmental apraxia of speech, furthermore, differed from the normal-speaking children on fricative prolongation and trisyllabic repetition rate, as well as on measures of trisyllabic repetitive performances (i.e. number of sequencing errors and number of attempts). The findings underscored the clinical importance of MPT for differential diagnosis, and for the quantification of degree of involvement in speech pathology.