Research suggests that select processing speed measures can also serve as embedded validity indicators (EVIs). The present study examined the diagnostic utility of Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) subtests as EVIs in a mixed clinical sample of 205 patients medically referred for neuropsychological assessment (53.3% female, mean age = 45.1). Classification accuracy was calculated against 3 composite measures of performance validity as criterion variables. A PSI ≤79 produced a good combination of sensitivity (.23-.56) and specificity (.92-.98). A Coding scaled score ≤5 resulted in good specificity (.94-1.00), but low and variable sensitivity (.04-.28). A Symbol Search scaled score ≤6 achieved a good balance between sensitivity (.38-.64) and specificity (.88-.93). A Coding-Symbol Search scaled score difference ≥5 produced adequate specificity (.89-.91) but consistently low sensitivity (.08-.12). A 2-tailed cutoff on the Coding/Symbol Search raw score ratio (≤1.41 or ≥3.57) produced acceptable specificity (.87-.93), but low sensitivity (.15-.24). Failing ≥2 of these EVIs produced variable specificity (.81-.93) and sensitivity (.31-.59). Failing ≥3 of these EVIs stabilized specificity (.89-.94) at a small cost to sensitivity (.23-.53). Results suggest that processing speed based EVIs have the potential to provide a cost-effective and expedient method for evaluating the validity of cognitive data. Given their generally low and variable sensitivity, however, they should not be used in isolation to determine the credibility of a given response set. They also produced unacceptably high rates of false positive errors in patients with moderate-to-severe head injury. Combining evidence from multiple EVIs has the potential to improve overall classification accuracy. (PsycINFO Database Record

Time-to-completion cutoffs are valuable additions to both tests. They can function as independent validity indicators or enhance the sensitivity of accuracy scores without requiring additional measures or extending standard administration time.

This study was designed to examine the clinical utility of critical items within the Recognition Memory Test (RMT) and the Word Choice Test (WCT). Archival data were collected from a mixed clinical sample of 202 patients clinically referred for neuropsychological testing (54.5% male; mean age = 45.3 years; mean level of education = 13.9 years). The credibility of a given response set was psychometrically defined using three separate composite measures, each of which was based on multiple independent performance validity indicators. Critical items improved the classification accuracy of both tests. They increased sensitivity by correctly identifying an additional 2-17% of the invalid response sets that passed the traditional cutoffs based on total score. They also increased specificity by providing additional evidence of noncredible performance in response sets that failed the total score cutoff. The combination of failing the traditional cutoff, but passing critical items was associated with increased risk of misclassifying the response set as invalid. Critical item analysis enhances the diagnostic power of both the RMT and WCT. Given that critical items require no additional test material or administration time, but help reduce both false positive and false negative errors, they represent a versatile, valuable, and time- and cost-effective supplement to performance validity assessment.

This study was designed to investigate the effects of timing on the likelihood of failing the Recognition Memory Test-Words (RMT) and Word Choice Test (WCT). The RMT and WCT were administered in counterbalanced order either at the beginning (Time 1) or at the end (Time 2) of a test battery to a mixed clinical sample of 196 patients (M = 44.5 years, 55.1% female) medically referred for neuropsychological evaluation. The risk of failing the accuracy score was higher at Time 1 on both the RMT (relative risk [RR]: 1.44-1.64) and the WCT (RR: 1.21-1.50) across a range of cutoffs. Likewise, the risk of failing the time-to-completion score was higher at Time 1 on both the RMT (RR: 1.30-1.94) and the WCT (RR: 1.58-3.75). Established cutoffs failed to reach specificity standards at Time 1; more liberal cutoffs cleared specificity thresholds at Time 2. According to our findings, the RMT and WCT may be prone to false-positive errors at Time 1. Conversely, when administered at Time 2, existing cutoffs may have lower sensitivity, but they are highly specific to invalid performance. Timing should be considered during both test selection and the interpretation of RMT and WCT scores. Using conservative cutoffs for morning administrations and liberal cutoffs for afternoon administrations may be necessary to neutralize timing artifacts. (PsycINFO Database Record (c) 2018 APA, all rights reserved).