The actual statements used in the IDI are responses generated from a group of nationally and globally culturally diverse individuals who participated in in-depth interviews with a cross-culture/cross-gender team of interviewers about how they experience cultural differences. The IDI items were not generated by the researchers. This provides evidence for the content validity of the items and counters possible criticism of systematic cultural bias being introduced by the researchers in the wording of the items. Content validity is the extent to which the items on an assessment are representative of the content being investigated. In the case of the IDI, the extent to which the items on the IDI are representative of the content of the Intercultural Development Continuum.
Also, rigorous Differential Item Function (DIF) analysis (a method to evaluate whether different subgroups respond differently to particular items within a scale) found no cultural bias in the IDI items. In the DIF analysis, the performance of respondents on each item were reviewed to evaluate if the item appeared to unfairly favor one group over another (e.g., cultural bias) in the items on the IDI.
For more information, please see the information and accompanying articles in the validation section of our website: https://idiinventory.com/idi-validation/