Histograms of Student Scores on the Quality and Culture Quiz (QCQ)*
* There is a right shift in the direction of higher scores in the post-QCQ distribution compared to the pre-QCQ. 66.7% of students improved their score by 1–5 points, as shown in C.
A. Pre-QCQ scores, unpaired group. B. Post-QCQ scores, unpaired group. C. Score difference (post-pre), paired group.