Simply stated, polygraph tests that cover multiple issues (not related to a specific incident) may show substantially reduced accuracy and efficiency. The risk of error ¬increases to the extent that the test includes a number of separate issues that can be independently answered truthfully or deceptively. Such tests are problematic when the individual is truthful to some relevant questions and deceptive to others.
A field study done for the U.S. Secret Service (Source: Raskin, Kircher, Honts, & Horowitz, 1988) revealed that accuracy declines when the examinee answers one or more questions truthfully and one or more deceptively for tests with multiple issues. This data argues against conducting a polygraph test that covers a range of issues, such as drug use, theft, bribery, or other criminal activity, etc.
The field study cited above looked at individuals that were either truthful or deceptive to all relevant questions vs. those in which the person was truthful to at least one relevant question and deceptive to at least one other relevant question. For those subjects, almost half of the outcomes were inconclusive (49%) and only 74.5% of decisions were correct.
The American Polygraph Association (APA) cites a study that indicates levels of accuracy as high as 93%. That study was based on polygraph tests done for “event-specific diagnostic examinations used for evidentiary purposes.” In other words, that study cites data from event-specific tests that are part of an interview, based on evidence; in other words, they involve one event with various, specific issues related to that event.
EyeDetect uses a test format known as the Relevant Comparison Test (RCT), which was developed for an automated polygraph screening system; the RCT covers two unrelated relevant issues. As such, an EyeDetect test determines a person’s behavior on an issue, not their guilt on one specific event. Responses to the relevant issue are compared by the algorithm to responses about a secondary issue.
A polygraph test that attempts to determine behavior on multiple, potentially unrelated issues, is less accurate because in that exploratory polygraph interview, the examinee may be questioned about separate issues for which s/he may be guilty on some issues and not on other issues. In those cases, there are too many potentially unrelated issues being compared.
EyeDetect is more accurate for screening (determining behavior) because of the use of comparison questions related to two similar, but likely unrelated issues.