four response categories (0, 1, 2, 3+ yes answers) for the age groups spanning from 18 to 32 years. The youngest age group was not included, since in this group the frequency of two or more yes answers was too low. Including more response categories did not change the results. Dropping the terms for genetic innovation did not worsen the model fit significantly for the CAGE as trichotomy (χ2 (4) = 0.530; p = 0.971), nor when the CAGE was analyzed with four response categories (χ2(4) = 0.681, p = .954). This renders lack of power as an explanation for the absence of genetic innovation, unlikely.
