Information processing speed is commonly measured in intelligence and neuropsychological testing, and the scores from speed measures are considered in diagnostic and management recommendations for students with academic learning problems. However, this score usage often depends on assumptions about strong relationships between cognitive speed and the ability to perform actual academic tasks under time pressure. The primary purpose of the present study was to test the strength of these relationships empirically. In the present study, children with prior learning disability diagnoses (146 girls and 301 boys, ages 10-14 years old) completed diagnostic batteries that included measures of cognitive speed as well as timed academic skills. The relationships between the two types of measures were often modest (median r = 0.25), and the gap between processing speed and timed academic scores was typically approximately 1 standard deviation. The pattern of relationships suggested that superficial similarity in stimuli and task demands affected the strength of associations. These results suggest that timed academic skills cannot be reliably estimated based on processing speed scores, and there will often be significant gaps between the two. Therefore, making diagnostic judgments (e.g., learning disability diagnoses) or management recommendations (e.g., for extended time testing accommodations) should be based on more direct measures of relevant academic skills.
Keywords: Academic skills; assessment; processing speed.