Validation of grooved pegboard cutoffs as an additional embedded measure of performance validity

Abstract

Objective Using embedded performance validity (PVT) comparisons, Erdodi et al. suggested that Grooved Pegboard (GPB) T-score cutoffs for either hand ( 29) or both hands ( 31) could be used as additional embedded PVTs. The current study evaluated the relationship between these proposed cutoff scores and established PVTs (Medical Symptom Validity Test [MSVT]; Non-Verbal Medical Symptom Validity Test [NV-MSVT], and Reliable Digit Span [RDS]). Method Participants (N = 178) were predominately Caucasian (84%) males (79%) with a mean age and education of 41 (SD = 11.7) and 15.8 years (SD = 2.3), respectively. Participants were stratified as “passing” or “failing” the GPBviaErdodi’s proposed criteria. “Failures” on the MSVT, NV-MSVT, and RDS were based on conventional recommendations. Results Moderate correlations between GPB classification and a condition of interest (COI; i.e. at least two failures on reference PVTs) were observed for dominant (χ2 (1, n = 178) = 34.72, ϕ = .44, p < .001), non-dominant (χ2 (1, n = 178) = 16.46, ϕ = .30, p = .001), and both hand conditions (χ2 (1, n = 178) = 32.48, ϕ = .43, p < .001). Sensitivity, specificity, and predictive power were generally higher than Erdodi et al.’s initial findings. Conclusion These findingsprovide supportfor the clinical utility of the GPB as an additional embedded PVT. More specifically, dominant and both hand cutoffs were found to be more robust measures ofnon-genuine performance in those without motor deficits. While promising, sensitivity continues to be low; therefore, it is ill-advised to use the GPB as a sole measure of ­performance validity.