This interpretation has been shown to be common among teachers who have participated in empirical studies aiming to design effective CDM reports for classroom use (Dhaliwal, Hembry, & Bradshaw, 2016; DiCerbo & Kobrin, 2016).Results from Dhaliwal et al. showed this interpretation was offered by teachers not only before the research team provided explanations of the probability of mastery as a degreeof certainty, but also persisted after desired interpretations were provided. Because the percent correct interpretation is so commonly the correct interpretation for teacher-madeclassroom assessments, it seems reasonable that teachers would misappropriate this interpretation to the probability of mastery.