chart identification

What Is Chart Identification?

Chart identification refers to the system of labels, numbers, and metadata that uniquely identify each polygraph chart collected during an examination. Proper chart identification ensures that every chart can be linked to the correct examinee, examination, and sequence position within the session, which is essential for scoring, quality control review, and legal proceedings.

Standard Identification Elements

A properly identified chart typically includes: the examinee's name or case identifier, the date of the examination, the examiner's name or identification number, the chart sequence number (Chart 1, Chart 2, etc.), the test format or technique being used, and the question sequence for that chart. In digital systems, this information is embedded in the file metadata and displayed in headers.

Importance for Scoring and Review

During numerical scoring, the examiner must score each chart in sequence and track scores across charts. Correct chart identification prevents scoring errors that could occur from processing charts out of order or confusing charts from different examinees. During blind chart analysis, proper identification (minus case information) allows the reviewer to score charts in the correct sequence while maintaining blindness to case details.

Legal and Archival Requirements

Polygraph charts may be entered as evidence in legal proceedings, reviewed by opposing experts, or examined years after the original testing. Complete chart identification creates an unbroken chain of documentation linking each piece of physiological data to the specific examination event. The APA Standards of Practice require that examination records — including all charts — be retained and properly documented. The examination report should reference chart identification to support the documented findings.