A Critical Analysis of the Nelson Denny Reading Test as a Method of Identifying Reading Impairment in Adults

Abstract

Disability-related test accommodations are requested frequently, especially at the postsecondary level and on licensing examinations. Access to such accommodations typically relies on proof of impairment in some area of academic functioning. The Nelson Denny Reading Test (NDRT; Brown, Fishco, & Hanna, 1993a, 1993b) is often employed by clinicians in order to demonstrate the need for extra time accommodation. The NDRT employs grade-based norms, meaning that postsecondary and graduate-level students who take the test are compared not with all of their same-aged peers but rather to a rarefied group of individuals who have achieved equally high levels of education. This leads to a skewed distribution of scores that, in turn, makes otherwise normally functioning individuals appear impaired. Employing the actual normative data from the NDRT, this study investigated the effect that use of such grade-based norms has on ratings of normative and relative impairment. With the same raw score, substantially more individuals would be classified as impaired on a measure of timed reading comprehension when higher grade level norms are applied as compared with norms that represent a broader sample of individuals. These findings demonstrate clearly that grade-based norms should not be employed when using the NDRT to determine disability-related normative impairment.