Teachers of first-year medical students identified possible reasons for poor performance. This exposed several beliefs about students. These beliefs were tested by comparing student attitudes with their exam performance. The findings question most of the teachers' beliefs. There does appear to be a link between exam performance and two factors: style of study and external commitments, such that the more knowledgeable students were about the type of study expected the better they performed, and the more they were affected by external commitments, the worse they did. However, other beliefs, such that students are more likely to fail because they live at home or are motivated by something other than a desire to "do good", were not found to be true. (Contains 8 figures.)