Measuring Domain-Specific Knowledge: From Bach to Fibonacci

Along with crystallized intelligence (Gc), domain-specific knowledge (Gkn) is an important ability within the nomological net of acquired knowledge. Although Gkn has been shown to predict important life outcomes, only a few standardized tests measuring Gkn exist, especially for the adult population. Complicating things, Gkn tests from different cultural circles cannot simply be translated as they need to be culture specific. Hence, this study aimed to develop a Gkn test culturally sensitive to a German population and to provide initial evidence for the resulting scores' psychometric quality. Existing Gkn tests often mirror a school curriculum. We aimed to operationalize Gkn not solely based upon a typical curriculum to investigate a research question regarding the curriculum dependence of the resulting Gkn structure. A set of newly developed items from a broad range of knowledge categories was presented online to 1450 participants divided into a high (fluid intelligence, Gf) Gf (n = 415) and an unselected Gf subsample (n = 1035). Results support the notion of a hierarchical model comparable to the one curriculum-based tests scores have, with one factor at the top and three narrower factors below (Humanities, Science, Civics) for which each can be divided into smaller knowledge facets. Besides this initial evidence regarding structural validity, the scale scores' reliability estimates are reported, and criterion validity-related evidence based on a known-groups design is provided. Results indicate the psychometric quality of the scores and are discussed.