FIG. 3. Total number of knots tied versus Mental Rotations Test score. A regression plot illustrating the total number of 1-handed surgical reef knots tied during three 10-minute training/repetition sequences versus the Vandenberg and Kuse Mental Rotations Test scores of preclerkship medical students in both the computer-based self-directed learning group (grey) and the didactically trained group (black). The log-transformed Pearson correlations were r = 0.42, p < 0.05; r = 0.45, p < 0.01) for the computer-based and didactic groups, respectively. Fifty-one points are shown as a result of 9 individuals having equivalent Mental Rotations Test scores and total number of knots tied.