Investigating the Relationship Between Vocabulary Knowledge and Academic Reading Performance: An Assessment Perspective

The present study was conducted in the context of Test of English as a Foreign Language (TOEFL) 2000 research to conceptually validate the roles of breadth and depth of vocabulary knowledge in reading comprehension in academic settings and to empirically evaluate a test measuring three elements of the depth dimension of vocabulary knowledge, namely, synonymy, polysemy, and collocation. A vocabulary size measure and a TOEFL vocabulary measure were also tested. The study found that the dimension of vocabulary depth is as important as that of vocabulary size in predicting performance on academic reading and that scores on the three vocabulary measures tested are similarly useful in predicting performance on the reading comprehension measure used as the criterion. The study confirms the importance of the vocabulary factor in reading assessment.