FORWARD AND BACKWARD MEMORY SPAN SHOULD NOT BE COMBINED FOR CLINICAL ANALYSIS

The practice of combining forward and backward memory span, as represe nted so prominently on the various Wechsler Scales, to arrive at a com posite score for clinical interpretation is examined historically and actuarially using a large (N = 1,342) nationally stratified random sam ple of children from ages 5 years through 19 years. Past literature do es not support the additive nature of forward and backward memory span as elements of a common process. Factor analyses of forward and backw ard recall using both digits and letters indicate that the two memory processes are distinct as well and should not be combined for clinical interpretation. (C) 1997 National Academy of Neuropsychology.