Albuminuria has been associated with lower cognitive functioning in some studies, but not in others. Reviews1,2 and editorials3 have discussed possible reasons for mixed results. Variable sample sizes, limited test batteries, different study populations and experimental designs, and variable adjustment for cardiovascular risk factors and other comorbid conditions may contribute to inconsistent findings. The study by Martens et al4 in this issue of AJKD supports a relationship between albuminuria and cognitive functioning and addresses a number of these methodological issues.