Clinical utility of reliable digit span in assessing effort in children and adolescents with epilepsy.

The assessment of effort is an important aspect of a comprehensive neuropsychological evaluation, as this can significantly impact data interpretation. While recent work has validated the appropriateness of adult-derived cutoffs for standalone effort measures in younger populations, little research has focused on embedded effort measures in children. The present study includes 54 clinically referred children and adolescents (32 males/22 females; aged 6-17) with a confirmed diagnosis of epilepsy. Reliable Digit Spans (RDSs) were calculated and the Test of Memory Malingering (TOMM) was administered in the context of a comprehensive neuropsychological evaluation. Using a previously published RDS cutoff of ≤6, a pass rate of only 65% was obtained, well below the recommended 90% pass rate for an effective effort index. In contrast, when adult criteria were used on TOMM Trial 2, a 90% pass rate was observed. RDS scores were significantly correlated with IQ estimates (r = .59, p < .001) and age (r = .61, p < .001). The difference between RDS and the TOMM on the participant outcome was statistically significant (χ(2) = 9.05, p = .003). These results suggest that RDS appears to yield a large number of false positives and, therefore, may be of limited utility in detecting poor effort in a pediatric epilepsy population. These findings likely extend to other pediatric populations that are known to have significant cognitive loss.