This paper examines the differences correlation between instructor- and peer-based participation scores and oral proficiency in an EFL course focusing on oral communication. It finds that there is very little correlation between instructor-based and peer-based participation scores (r = 0.187, p = 0.053) and that the former is more associated with improvement in fluency (r = 0.266, p = 0.005), but that the latter is strongly associated with pre-class levels of fluency measures such as trimmed speech rate (r = 0.364, p < 0.001). However, neither measure of participation was particularly correlated with post-class levels of fluency. Therefore, some caution is required by instructors when using in-class participation scores. While it is important to encourage students to improve by participating in classes, the methods of assigning participation scores examined in this paper may not be appropriate as a part of the composite final grade in the class as they do not correlate well to final skill level.