Each QC Test Item falls into one of the following categories:
A QC Item specifying a Test that must be performed due to requirements set by a regulator or government. Has a published reference document or standard.
Defined in a standards document including a standard scale. May have a defined pass/fail threshold. As a user, I ought to be able to compare the results of different QC devices and see the same result.
Measurable in a quantitative way against a defined scale, but no standard threshold is agreed. There may be no formal spec or standard, but an agreed method is implied by or exists in the test definition. As a user, I ought to be able to compare the results of different QC devices if I configure the same thresholds.
May be measurable but with only a medium degree of confidence. A failure threshold is not defined, or is very vague. May require human interpretation of results. As a user, I cannot expect different QC devices to report identical results.
Gold coloured cards are used for Tests that can only be carried out by human eyes or ears (Golden Eyes and Golden Ears) or where a human is required to fully interpret the results of an automated QC tool.