Fig. 5.

Distributions of the total scores of 3 items. a Low ratio group (items 1, 4, and 6), (b) middle ratio group (items 1, 3, and 5), and (c) high ratio group (items 2, 3, and 5) on a normal scale. d Low ratio group, (e) middle ratio group, and (f) high ratio group on a semi-logarithmic scale. While all distributions of the three groups were right-skewed, the frequencies of the zero score differed between groups (a, b, and c). Using semi-logarithmic scales, all three groups showed linear patterns with similar gradients. At the lowest end of the scores, the distribution for the low ratio group (d) exhibited higher frequencies than predicted from the linear pattern, while the distribution for the high ratio group (f) exhibited lower frequencies than predicted from the linear pattern. The divergence of the actual data from the predicted linear pattern at the lower end of the distribution was not evident for the middle ratio group (e)