Fig. 3

a. Item complexity and probability of creating a difficult, discriminating question. The probability of creating a difficult, discriminating question (< 80 % correct; > 0.20 discrimination index) increased with increasing item complexity (cognitive level I-IV). (Letters indicate statistical p < 0.028 differences among levels of item complexity). b. Item complexity and probability of creating an easy and non-discriminating question. The probability of creating an easy and non-discriminating question (> 90 % correct; <0.15 discrimination index) decreased with increasing item complexity (cognitive level I-IV). (Letters indicate statistical p < 0.028 differences among levels of item complexity)