Background: Universities in Thailand are preparing for Thailand's integration into the ASEAN Economic Community (AEC) by increasing the number of tests in English language. English language is not the native language of Thailand Differences in English language proficiency may affect scores among test-takers, even when subject knowledge among test-takers is comparable and may falsely represent the knowledge level of the test-taker.
Objective: To study the impact of English language multiple choice test questions on test scores of medical students.
Material and method: The final examination of fourth-year medical students completing internal medicine rotation contains 120 multiple choice questions (MCQ). The languages used on the test are Thai and English at a ratio of 3:1. Individual scores of tests taken in both languages were collected and the effect of English language on MCQ was analyzed Individual MCQ scores were then compared with individual student English language proficiency and student grade point average (GPA).
Results: Two hundred ninety five fourth-year medical students were enrolled. The mean percentage of MCQ scores in Thai and English were significantly different (65.0 ± 8.4 and 56.5 ± 12.4, respectively, p < 0.001). The correlation between MCQ scores in Thai and English was fair (Spearman's correlation coefficient = 0.41, p < 0.001). Of 295 students, only 73 (24.7%) students scored higher when being tested in English than in Thai language. Students were classified into six grade categories (A, B+, B, C+, C, and D+), which cumulatively measured total internal medicine rotation performance score plus final examination score. MCQ scores from Thai language examination were more closely correlated with total course grades than were the scores from English language examination (Spearman's correlation coefficient = 0.73 (p < 0.001) and 0.53 (p < 0.001), respectively). The gap difference between MCQ scores in both languages was higher in borderline students than in the excellent student group (11.2 ± 11.2 and 7.1 ± 8.2, respectively, p < 0.001). Overall, average student English proficiency score was very high, at 3.71 ± 0.35 from a total of 4.00. Mean student GPA was 3.40 ± 0.33 from a possible 4.00. English language MCQ examination scores were more highly associated with GPA than with English language proficiency.
Conclusion: The use of English language multiple choice question test may decrease scores of the fourth-year internal medicine post-rotation final examination, especially those of borderline students.