Testing the robustness of the diagnostic overshadowing bias

The robustness of the diagnostic overshadowing bias was examined by (a) testing the relation of overshadowing to level of mental retardation, (b) reexamining the effect of clinical experience in a more sensitive analysis, and (c) extending previous results to rehabilitation counselors. Diagnostic overshadowing was found with individuals with an IQ of 58, but did not generalize to those with IQs 70 or 80. This finding does not support the saliency hypothesis proposed by Reiss and his colleagues. In contrast to earlier studies, experience was related to overshadowing, although results were mixed. Experience measured by number of clients seen was not significant, whereas longevity in the field of mental retardation was associated with increased overshadowing.