Aging and the Stroop effect: a meta-analysis.

In this meta-analysis, data from 20 studies comparing younger and older adults on the Stroop interference effect, contained in 15 articles, were analyzed. No significant difference was found in the Stroop interference effect, expressed as mean standardized difference, between the 2 age groups (for younger adults: d = 2.04; for older adults: d = 2.17). Moderator variables were present, but these did not produce age differences. Brinley analysis showed that a single regression line with a slowing factor of 1.9 described the data well (R2 = .83) and confirmed that no Age x Condition interaction was present in the data. Likewise, no Age x Condition interaction was found when the data were fitted to the information loss model; the age ratio of decay rates was estimated to be 1.4. Consequently, the apparent age-sensitivity of the Stroop interference effect appears to be merely an artifact of general slowing.