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There has been discussion lately about whether bootstrap versus permutations methods are the more appropriate in diagnostic psychophysiology, especially in the context of concealed information tests (CITs), also called guilty knowledge tests (GKTs). We review the use of bootstrapping in most published CIT/GKT studies (where means, or correlations, as opposed to peak amplitudes are estimated) and find them valid and reliable. When bootstrapping and permutations were applied to the same synthesized ERP datasets, they agreed 98.1% of the time, averaged over 24,000 iterations. [ABSTRACT FROM AUTHOR]

The Complex Trial Protocol (CTP), was shown to be an improvement over the previous 'three stimulus' P300-based concealed information tests (CITs). Not only was it highly accurate with autobiographical information but was also resistant to the use of countermeasures (CMs). The current study applied the CTP to the detection of incidentally acquired information in a mock crime scenario. In previous 'three stimulus' mock crime studies utilizing P300-based CITs, participants memorized a guilty knowledge item(s). Special care was taken in the current study to ensure that participants' knowledge of the guilty item in the mock crime was obtained only during the commission of the act in order to bolster ecological validity. Overall, 92% of all participants in guilty, innocent, and countermeasure conditions were correctly classified. CM use was again indexed by reaction times (RTs). [ABSTRACT FROM AUTHOR]