title: Detection of suboptimal effort with symbol span: development of a new embedded index.
abstract: Developing embedded indicators of suboptimal effort on objective neurocognitive testing is essential for detecting increasingly sophisticated forms of symptom feigning. The current study explored whether Symbol Span, a novel Wechsler Memory Scale-fourth edition measure of supraspan visual attention, could be used to discriminate adequate effort from suboptimal effort. Archival data were collected from 136 veterans classified into Poor Effort (n = 42) and Good Effort (n = 94) groups based on symptom validity test (SVT) performance. The Poor Effort group had significantly lower raw scores (p < .001) and age-corrected scaled scores (p < .001) than the Good Effort group on the Symbol Span test. A raw score cutoff of <14 produced 83% specificity and 50% sensitivity for detection of Poor Effort. Similarly, sensitivity was 52% and specificity was 84% when employing a cutoff of <7 for Age-Corrected Scale Score. Collectively, present results suggest that Symbol Span can effectively differentiate veterans with multiple failures on established free-standing and embedded SVTs.
authors.affiliation: Memphis Veterans Affairs Medical Center, Memphis, TN 38104, USA. john.young5@va.gov
authors.forename: J Christopher
authors.initials: JC
authors.lastname: Young
authors.forename: Joshua E
authors.initials: JE
authors.lastname: Caron
authors.forename: Brandon C
authors.initials: BC
authors.lastname: Baughman
authors.forename: R John
authors.initials: RJ
authors.lastname: Sawyer
mesh_terms: D000328:Adult; D000368:Aged; D001288:Attention / Q000502:physiology*; D003072:Cognition Disorders / Q000175:diagnosis*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008306:Malingering / Q000175:diagnosis* / Q000523:psychology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D011597:Psychomotor Performance; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014728:Veterans; D014888:Wechsler Scales; D055815:Young Adult