Educational level differences on the Mini-Mental State: the role of test bias.

Less educated elderly people are commonly found to perform more poorly on the Mini-Mental State Examination (MMSE). This educational level difference has been attributed by some research workers to test bias. To assess whether the MMSE is biased against the poorly educated, its validity was assessed separately in the more- and less-educated members of a community sample. No evidence was found to indicate that the test is a biased measure of cognitive impairment.