Classification of speech and language profiles in 4-year-old children with cerebral palsy: a prospective preliminary study

Abstract

Purpose: In this study, the authors proposed and tested a preliminary speech and language classification system for children with cerebral palsy.

Method: Speech and language assessment data were collected in a laboratory setting from 34 children with cerebral palsy (CP; 18 male, 16 female) with a mean age of 54 months (SD = 1.8). Measures of interest were vowel area, speech rate, language comprehension scores, and speech intelligibility ratings.

Results: Canonical discriminant function analysis showed that 3 functions accounted for 100% of the variance among profile groups, with speech variables accounting for 93% of the variance. Classification agreement varied from 74% to 97% based on 4 different classification paradigms.

Conclusions: The results of this study provide preliminary support for the classification of speech and language abilities of children with CP into 4 initial profile groups. Further research is necessary to validate the full classification system.

Figures

Figure 1

Schematic model of hypothesized communication profile groups.

Figure 2

Schematic model of communication profile groups examined in this study.

Figure 3

Vowel space area by Profile Group. Profile Group NSMI refers to children with no speech motor involvement; Profile Group SMI-LCT refers to children with speech motor involvement and age appropriate (typically developing) language skills; Profile Group SMI-LCI refers to children with speech motor involvement and language impairment. Note that children in Profile Group ANAR (all of whom were unable to speak) did not contribute vowel space data. Vowel area is measured in Hz2

Figure 4

Speech rate by profile group. Profile Group NSMI refers to children with no speech motor involvement; Profile Group SMI-LCT refers to children with speech motor involvement and age appropriate (typically developing) language skills; Profile Group SMI-LCI refers to children with speech motor involvement and language impairment. Note that children in Profile Group ANAR (all of whom were unable to speak) did not contribute speech rate data. Rate data are measured in syllables per minute and are based on the duration of recited utterances, including all pauses.

Figure 5

Speech intelligibility ratings by profile group. Profile Group NSMI refers to children with no speech motor involvement; Profile Group SMI-LCT refers to children with speech motor involvement and age appropriate (typically developing) language skills; Profile Group SMI-LCI refers to children with speech motor involvement and language impairment. Profile Group ANAR refers to children who were anarthric. Intelligibility ratings are based on a 7-point likert scale where 1 = difficult or impossible to understand and 7 = very easy to understand.

Figure 6

Language comprehension scores by profile group. Profile Group NSMI refers to children with no speech motor involvement; Profile Group SMI-LCT refers to children with speech motor involvement and age appropriate (typically developing) language skills; Profile Group SMI-LCI refers to children with speech motor involvement and language impairment. Profile Group ANAR refers to children who were anarthric. Standard language scores are based on a mean of 100 and a standard deviation of 15.

Figure 7

Canonical discriminant functions plotted by profile group.