How “Proficient” Is Proficient? Subjective Proficiency as a Predictor of Bilingual Listeners’ Recognition of English Words

PURPOSE: English proficiency must be considered when a bilingual individual is to be evaluated clinically with English speech material. This study describes the minimum level of self-reported English proficiency that identifies bilingual individuals who may perform on par with monolingual listeners on an English word recognition test. METHOD: A total of 125 normal hearing bilingual listeners rated their English proficiency in listening, speaking, and reading on an 11-point scale. Other related linguistic variables were also obtained. A randomly selected Northwestern University Auditory Test No. 6 (NU-6) list (50 English monosyllabic words) was presented to all participants at 45 dB HL in quiet. RESULTS: Over 90% of the listeners self-rated to have at least "good" proficiency in English listening, speaking, or reading. Of these participants, more than 30% did not achieve a monolingual normative level in English as delimited by binomial distribution. Composite proficiency ratings across language domains better predicted word recognition performance than self-ratings for listening proficiency only. Combining language dominance and age of English acquisition with proficiency ratings further improved prediction specificity. CONCLUSIONS: Self-rated English proficiency can predict bilingual listeners' performance on the NU-6 test. For desirable sensitivity and specificity in predicting monolingual-like performance, a minimum rating of 8 out of 10 across all language domains is recommended.