Within the school psychology literature, it is frequently asserted that deficits in cognitive processing are a defining characteristic of children with academic dysfunction, and establishing links between relevant cognitive and academic weaknesses is a core pillar of patterns of strengths and weaknesses assessment models. Accordingly, the present study employed diagnostic utility statistics to determine whether the presence of a significant cognitive weakness accurately distinguishes between participants with and without academic weaknesses ages 7 years 0 months to 18 years 11 months in the linked Kaufman Assessment Battery for Children--Second Edition (Kaufman & Kaufman, 2004a) and Kaufman Test of Educational Achievement--Second Edition (Kaufman & Kaufman, 2004b) normative sample. Sensitivity and positive predictive values for the CHC-related broad abilities ranged from low to moderate, indicating that a cognitive weakness may not be robust a rule-in indicator for the presence of an academic weakness. Conversely, specificity and negative predictive values were consistently high, indicating that, absent a cognitive weakness, it is unlikely that an individual will present with an academic weakness. Potential implications for clinical assessment are discussed.