Language Comprehension Tests.
APPROVED BY THE MEMBERS OF THE THESIS COMMITTEE:( ~ The purpose of this study was to determine the relationship between the Peabody Picture Vocabulary Test-Revised, (PPVT-R) and receptive subtest of the Preschool Language Scale (PLS), and between the PPVT-R and the Test of Auditory Comprehension of Language-Revised (TACL-R), as well as determine how the tests compare in identifying children in need of further evaluation in the area of receptive language.The reasoning behind the goal of this study was to determine that if the three tests showed a strong, positive correlation and identified the same children as needing further assessment, then perhaps the test which was easier and shorter to administer (the PPVT-R) could be used with more confidence 2 as a quick, reliable screening tool of overall receptive language ability.In other words, if a child does poorly on the PPVT-R, one could assume that the child would most likely score below average on the other two tests also. Based on the results of this study, one cannot make this assumption.The subjects in this study included 10 males and 15females. All were preschool students, ranging in age from 4-1 to 4-11 with a mean age of 4-6 years. The subjects weregiven three tests in counterbalanced order. The mean age equivalents and standard scores were determined for all three tests and percentiles were determined for the PPVT-R and TACL-R.The Pearson product moment correlation coefficient (Pearson£) was used to determine the degree of relatedness among the tests. A moderate positive correlation of .41 was found between the PPVT-R and PLS, and a low positive correlation of .27 was found between the PPVT-R and TACL-R.
Shared variance (£ 2 ) was 17% between the PPVT-R and PLSand 7% between the PPVT-R and the TACL-R.In determining how the tests identify children needing further evaluation of receptive language skills, cut-off criteria of total age equivalent 2 years and 1 year below chronological age, as well as percentile scores below the 20th and 10th percentile (for the PPVT-R and TACL-R) were 3 used. The results indicated that only 2 of the 25 children in this study showed need for further evaluation. These were identified by the TACL-R, but not by the PPVT-R or PLS.These results seem to indicate that, based on these study results alone, one cannot use the results of any one of the tests administered as a predictor of another. However, these results may have been affected by the sample used for this study.Higher correlations and identification of more children needing further evaluation could result from use of a different, larger sample due to a greater chance that a "true" mean performance would occur given a larger, more diverse sample population.