Before revision:  Cultural, age and gender bias were assessed on item level using differential item functioning (DIF) and on scale level by calculating correlations between IADL and cognitive and functional measures . RESULTS: We did not find meaningful bias on item or on scale level, as indicated by low DIF effect sizes (  R2 range 0-0.03) and correlations in expected directions and of similar magnitude.
After revision:  Cultural, age and gender bias were assessed on item level using differential item functioning (DIF) and on scale level by calculating correlations between IADL and cognitive and functional measures . RESULTS: There were some differences in activity endorsement. A few items showed statistically significant DIF. However, there was no evidence of meaningful item bias: effect sizes were low ( R2 range 0-0.03) and correlations in expected directions and of similar magnitude.