Describe in detail polygraph-based evaluation?

what is the usefulness of the polygraph-based evaluation?

A polygraph, often incorrectly referred to as a lie detector test, is a device or procedure that measures and records several physiological indicators

Polygraphs and Lie Detection

A polygraph is a device that collects and enables the analysis of human physiological responses through sensors physically connected to the individuals examined by this system. Polygraphs are employed to detect deception while the examinee answers a set of questions