Age and education effects on brain-damaged subjects: 'Negative' findings revisited

In a recent publication Reitan and Wolfson (1995) report on the results of research in which they identify minimal effect for age and education on brain-damaged subjects. The purpose of the present article was to expand considerably on the cautionary comments expressed by these authors for their findings, with respect to (1) the problem of non-differentiated brain-damage samples both in terms of type and severity of neuropathology, and (2) psychometric issues, particularly in terms of the possibility of a Type Il error (false negative results). An argument is presented which suggests that the relative absence of positive findings in the Reitan and Wolfson research is inconsistent with current theoretical and research indications of a high probability for compromised neuropsychological function in brain-damaged populations due to older age and lower education effects.