Which types of polygraph test are there?

In America, polygraph tests are primarily used by government agencies and the criminal justice system. They are also used for civil cases and to combat insurance fraud. A polygraph is a device that amplifies certain physiological signals, such as blood pressure, palm sweating and respiration. Polygraph techniques are not objective, not standardized and they do not have norms. What the examiners do is look for physiological responses that are associated with lying based on how people respond to different types of questions. Three types of tests can be done with the polygraph:

• Employee screening tests. This test is usually a relevant-irrelevant test (RIT). Here, employees are asked relevant questions about their work behavior, mixed up with questions that are irrelevant for the job. When a relevant question about for example drug use elicits a more pronounced response, employers often confront the subject. The RIT assumes that truth tellers respond strongly to irrelevant questions and not so strongly to relevant questions, or at the same level to all relevant questions. It also assumes liars respond more strongly to the relevant questions.
• Guilty knowledge test (GKT). This is also known as the concealed information test. During this polygraph test, people are asked factual questions about whether they are or are not involved in a crime. The questions are multiple choice and contain one guilty answer alternative that only the guilty person would know next to the examiner. It assumes that innocent people respond the same to all GKT answer alternatives, but a guilty person would respond more strongly to the guilty alternative. An alternative to the GKT is the event-related potential (ERP) variant. These methods ensure someone responds to all items so rapidly they do not have time to employ countermeasures.
• Comparison question technique (CQT). This technique is most often used in real life and most likely to be made available to mental health clinicians. The clinician designs questions related to an incident that took place, that can only be answered with yes or know. Truth tellers will respond more strongly to control or comparison questions, whereas deceptive individuals will respond more strongly to the relevant questions. This is because truth tellers know they are telling the truth on the relevant questions about the crime, as they have not committed it. Thus, they fear lying on the control or comparison questions more. For deceptive individuals, the relevant questions pose more of a threat, as they are about a crime they have committed. This is why their responses will be bigger to the relevant questions, and less intense to the comparison questions. However, it is feared that that innocent individuals might also experience distress on the relevant questions when being falsely 'accused', thus the test is biased against the innocent. Another concern is that this test is very vulnerable to countermeasures, which are strategies that are deliberately adopted to change the outcome of the polygraph. These strategies can be found online by anyone.

What do people say about the accuracy of the CQT?

People within the polygraph profession insist that it is highly accurate. People a bit further from the profession however, believe that it is not standardized, objective or based upon a good theory. The accuracy levels of the CQT are often questioned by those outside the field.

Are there alternative methods to the polygraph?

There are alternative methods to the polygraph. However, these are not widely used. Examples are voice stress analysis or EEG. The reason they are not widely used is because they are not admissible in court as evidence.

What are the clinical applications of these tests?

Screening tests for employees are still widely used, as are control question tests. The latter one is often used in the case of sex crimes. Not only are they used for confessions, but they are also used to assess treatment success or check rule compliance. The control question tests are also used in possible child abuse cases. In the rapport, the examiner usually reports the allegations against a subject, what the questions asked were, and an explanation of what happened by the subject.

What are the different types of integrity testing?

Integrity testing is a type of testing where people fill out questionnaires that measures certain traits or behavioral tendencies that are associated with dishonesty or possible counterproductive behavior. These are often used for the screening of employees or personnel selection. There are two major categories of this preemployment screening, namely overt tests and personality oriented tests. Overt tests contain statements or questions that ask a person directly about how they feel about dishonesty or illegal activities. Personality oriented tests are tests that are 'veiled', they are used to predict counterproductivity rather than theft or dishonesty specifically and clearly.

Do integrity tests have good validity?

There are two types of validity that have to be good for integrity testing specifically. The first one is criterion-related validity. This type of validity is about whether integrity tests are doing what they are supposed to do; namely, identify those that are likely to engage in theft or counterproductive behaviors. This validity relates to whether a test is effective for the purpose that it was intended for. The second one is construct validity, which refers to whether the question actually measures the underlying psychological construct it wants to measure.

How do we measure criterion-related validity?

We measure criterion-related validity in two ways. The first one is self-report, for example when someone admits theft or counterproductive things like absenteeism. The second one is external criteria, for example documented days someone was late, broke something or terminations for wrongdoings like theft. This last measure has the problem that it is not sensitive; many counterproductive behaviors often go unnoticed or are not recorded.

How do integrity tests relate to basic personality traits?

Integrity tests relate to the Big Five: extraversion, neuroticism, agreeableness, conscientiousness and openness to experience. Conscientiousness appears to be the best predictor for all job related criteria. Extraversion appears especially important for job performance with jobs that involve a lot of social interaction. Openness to experience appears to be very important to how much people respond to job training, but not to job performance itself. Any personality traits related to dependability and trustworthiness appear to be very predictive of how well people do at their jobs.

However, integrity tests appear to go further than the Big Five. They measure an honesty factor that is not reflected in the Big Five through looking at fairness and sincerity. They also assess important aspects of self-control that are not included in the Big Five.

How does integrity relate to externalizing proneness?

Any trait that has to do with self-control stands opposite of externalizing psychopathology: addictive behaviors and impulsive-antisocial beahvior. Thus, scores on integrity tests reflect the variation that people show in externalizing vulnerability, or the variation in impulse control problems.

Are there any controversial aspects to integrity testing?

There are a few controversial aspects to integrity testing:

• Honest and dependable workers may be denied employment because they fail their integrity tests, or their scores fall below cut-off scores companies stick to for hiring. In other words, people that are not actually dishonest may be classified as such and thus be denied work. There is a problem with false positives.
• Integrity tests may be very vulnerable to people trying to fake being trustworthy. Thus, next to a problem with false positives, the integrity tests may also be vulnerable to false negatives due to people consciously deceiving.
• Integrity tests may also discriminate against protected groups. These protected groups, namely women, racial minorities or elderly people may possibly score higher on such tests by default, thus making it less likely they get hired.
• The questions asked on integrity tests may be an invasion of privacy of the respondent, especially the overt integrity tests, where direct questions about wrongdoings are asked.
• A related issue to the above one is that of informed consent. Often, when people apply for a job and they have to do an integrity test, informed consent is implied, but this must be balanced by the employers explaining why they have to.
• Integrity testing cannot be the primary basis for hiring or firing someone.

Are there other types of assessment?

Types of assessment that could be considered are gaming or VR approaches. These could be alternatives to self-report methods. An example of a possible computer approach is the Implicit Association Test (IAT). Another approach is to do tests of cognitive ability. A third option would be to add brain response measures into measures of integrity. The best option would be a multimethod approach in which brain response measures, self-report measures and beavhioral response variables are combined into one test of integrity.