This paper presents findings of a study of recognition vocabulary knowledge as a predictor of written Academic English Proficiency (AEP) and overall Academic Achievement in an English medium higher education program in an English-as-a-Foreign-Language (EFL) context. Vocabulary knowledge was measured using a Timed YES/NO (TYN) test. AEP was assessed using an academic writing test based on IELTS. Performance on these measures was correlated with Grade Point Average (GPA) as a measure of academic achievement for Arabic L1 users (N=70) at an English-medium College of Applied Sciences in the Sultanate of Oman. Vocabulary size and speed correlated with both academic writing and GPA measures. The combined vocabulary and writing measures were also examined as predictors of academic achievement. The TYN test is discussed as reliable, cost and time effective general measure of AEP and for showing if students have the necessary vocabulary knowledge to undertake study in a tertiary level English medium program.

This paper presents findings of a study of recognition vocabulary knowledge as a predictor of written Academic English Proficiency (AEP) and overall Academic Achievement in an English medium higher education program in an English-as-a-Foreign-Language (EFL) context. Vocabulary knowledge was measure...