Validity and Efficiency of the Check-Slash Transcription Method for Measuring Intelligibility

Speech-language pathologists are routinely called upon to make professional assessments concerning a speaker\u27s level of intelligibility. The use of subjective judgement procedures for estimating a percentage of intelligibility is the general practice of many speech-language pathologists because they require minimal time. Although efficient, these methods lack any form of numerical support, and their validity and reliability is questionable. The standard within the field that provides data support is the orthographic transcription method, but it is considered to be too time-consuming for practical application (Samar & Metz, 1988). Researchers continue to seek a measure that is both valid and efficient to be used clinically. The purpose of this study was to establish validity of a check-slash transcription method used to provide objective numerical support for assigning percentage of intelligibility for individuals with moderate speech impairments. The study sought to answer the following questions: 1) Is the check-slash method of transcription a valid measure for quantifying percentage of intelligibility? 2) Is the check-slash method a more time-efficient procedure than the orthographic transcription method? The subjects for this study were 20 graduate students from Portland State University, that were randomly assigned to two transcription groups (check-slash or orthographic}. Each listener transcribed 12 samples taken from 2 girls and 10 boys between the ages of 4:1 and 5:6 with a moderate degree of phonological deficiency. The data were analyzed using individual Mann-Whitney U Tests for each of the 12 samples. Results indicated no significant difference between the check-slash and orthographic transcription methods when used to assign a percentage of intelligibility to individuals with a moderate speech deficit. Although no significant difference was found, interrater reliability for both methods was low. This study established efficiency for the check-slash transcription method when compared to the orthographic method. Increased efficiency for the check-slash method ranged from 38% to 54% over the orthographic method. Results may also indicate that listener perception may influence each clinician\u27s ability to be accurate in their assessments