The term "culture-general" refers to frameworks that can be applied to any culture, for example, how individualistic or collectivist a group is; how a group thinks about and manages time; how a group organizes and thinks about power; how direct or indirect a group is, etc.
Culture-specific refers to aspects of specific cultures. For example, in US culture people tend to be more direct.
The IDI is designed and validated as a culture-general measure of intercultural competence. This means that the IDI is descriptive of a general orientation toward making sense of and responding to cultural differences generally and within particular cultural or group contexts. This is because people tend to maintain cognitive consistency in the way they construe cultural differences, both generally and specifically.
The IDI asks individuals to respond to the items in the assessment in terms of their own culture and other cultures. The IDI has been statistically validated to generalize across other cultural communities rather than the respondent’s own culture group. This means that the IDI provides a powerful and accurate profile of respondents’ orientations toward a wide range of “other culture” groups. Examples of these groups include nationality, ethnicity, gender, and other diversity categories.