AsiaTEFL Logo        The Journal of Asia TEFL
The Journal of Asia TEFL
Articles By Subject
Current Issue
Past Issues
Special Issue
Information of the Journal
Editorial Board
Submission Guidelines
Ethical Guidelines
Manuscript Submission
Journal Order
Today 3,820
Total 3,854,319
Current Issue
Go List

Volume 6 Number 2, Summer 2009, Pages 1-231   

PDF Download

How Many Words Do You Need to Know to Understand TOEIC, TOEFL & EIKEN? An Examination of Text Coverage and High Frequency Vocabulary

    Kiyomi Chujo and Kathryn Oghigian

In order to understand the meaning of a written text, it is generally accepted that a reader should understand an average of nineteen out of twenty words, and this is referred to as “95% coverage.” Given the popularity and importance of proficiency tests in second language acquisition, this study explores how much vocabulary a learner needs to know in order to be able to read and understand TOEIC, TOEFL and EIKEN proficiency tests. The vocabulary from several retired tests was compared to the vocabulary on three criterion lists: a high-frequency word list from the British National Corpus, the Standard Vocabulary List, and Nation's 14K word-family list. We were able to determine that in order to gain 95 percent coverage on TOEIC, a reader would need a minimum vocabulary size of 4,000 words, or 3,000 word families. TOEFL requires a 4,500-word vocabulary, or 3,500 word families, and a 5,500-word vocabulary, or 4,500 word families, is needed for EIKEN Pre-1st Grade. We also found that recent (2005/2006) versions of these tests require a smaller vocabulary compared to earlier versions. In addition, the SVL appears to provide a more accurate range of vocabulary for the lower level EIKEN tests but that a high correlation among results for the three criterion lists indicates these are stable and effective tools for determining text coverage vocabulary size.

Keywords: text coverage, vocabulary size, proficiency tests, criterion vocabulary lists