Figure 2

Behavior of difficulty and discrimination indices and possible countermeasures to be considered. It provides a guide for a view of investigation of causing factors. For example, when one indicator shows non-discrimination against a low difficulty index, in addition to investigations on ambiguous or incomplete aspect of the definition and a need for further training, investigations for consistency of the definition with the current condition of health system may be required. When the consistency is assured and the definition is found to be complete, an investigation on the difficulty among health workers of the indicator may be required. These investigations are expected to provide the most probable and influential factors for the health workers' confusion.