The value of the WISC-IV Digit Span subtest in detecting noncredible performance during pediatric neuropsychological examinations

In adult populations, research on methodologies to identify negative response bias has grown exponentially in the last two decades. Far less work has focused on methods appropriate for children. Although several recent studies have demonstrated the appropriateness of using stand-alone symptom validity tests with younger populations, a near absence of pediatric work has investigated embedded validity indicators. The present study examined the classification value of several scores derived from the WISC-IV Digit Span subtest. The sample consisted of 274 clinically referred mild traumatic brain injury patients aged 8 through 16 years. Fourteen percent of the participants failed both the Medical Symptom Validity Test and Test of Memory Malingering, which was used as the criterion for noncredible effort. For age-corrected scaled scores, a score of ≤5 resulted in the optimal cut-score, yielding sensitivity of 51% and specificity of 96%. For Reliable Digit Span, the optimal cut-score was ≤6, with sensitivity of 51% and specificity of 92%. Although only moderately sensitive, Digit Span scores are likely to have good utility in identifying noncredible performance in relatively high-functioning older children and adolescents. Indeed, classification statistics produced in this pediatric sample compare favorably with those produced in many real-world adult patients.