Examination of Criterion Validity about the Standard Language Test of Aphasia

Abstract

The Standard Language Test of Aphasia (SLTA) is the most frequently used comprehensive aphasia rating scale in Japan. Although the SLTA has been verified for reliability, verification for validity is inadequate. The purpose of this study was to examine criterion-related validity of the SLTA. The SLTA was performed on patients who had passed 3months or more after onset of the aphasia-causing disease such as stroke, and the Japanese version of the Western Aphasia Battery (WAB) was subsequently performed. We investigated age, gender, disease, and calculated Spearman's rank correlation coefficient for total score and each item of the SLTA and the WAB. There were 20participants (14males, 6females), with a mean age of 68.5±12.5years. Correlations of the SLTA and the WAB were as follows: SLTA total index score and WAB aphasia quotient; r=0.870 (P<0.001), SLTA Writing factor and WAB (VI) Writing; r=0.852 (P<0.001), SLTA writing instructions and WAB writing instructions; r=0.807 (P<0.001). Many of the correlations of Z-scores between sub-tests were r≥0.7. The SLTA has criteria-related validity and now the aphasia test that has been tested for reliability and validity. (Received July 22, 2019; Accepted March 4, 2020; Published July 1, 2020).