FIGURE 6.

Panel A shows a theoretical “obstacle course of cataract surgery” with relative difficulties of the steps represented by the column height. The surgeon risks to fail (have complication) when the skill level is lower than the column height for a particular surgical step. Of note, the height of the columns do not represent a scientific measure of difficulty, but are varied for illustrative purpose only, to convey the idea of an obstacle course. Panel B shows the CCC column relatively lowered by virtue of skill development for the step, thus the relative difficulty decreases. The other columns remain at the same height as in this illustration there is the assumption that there is no skill development for the other steps of cataract surgery. As a result, the learner can pass over the CCC column but has a risk of failure (complication) as s/he passes along the path of surgery with inadequate skill to pass over the columns representing the other surgical steps.