SYNLAB Laboratory Services has recently transitioned from ISO/IEC 17025:2005 to 17025:2017. A requirement of ISO/IEC 17025:2017 is that the laboratory provides information on decision rules and statements of conformity.
This blog aims to provide details on what they are and their significance to workplace drug and alcohol results.
Decision rules – The cut off levels that determine a positive or negative result
Statements of conformity – Statement sent to customers explaining if a result is positive or negative
Cut-off levels – The level used to determine if an analyte is positive or negative provided by the UK Workplace Testing Guidelines.
Functional cut-off levels – These are the cut-off levels provided by the UK Workplace Testing Guidelines with the uncertainty of measurement applied.
HOW DECISION RULES ARE APPLIED
When a customer requests a statement of conformity to a specification or standard, the decision rule, along with the specification or standard, will be clearly stated.
The decision rule that SYNLAB Laboratory Services employs is the functional cut-off level. This is the cut off defined in the Workplace Testing Guidelines, the measurement of uncertainty is then added to this. A result above the functional cut off level will be classed as positive, while a result below the cut off level will be classed as positive.
A full list of the substances we test for and the cut off levels can be found in our Technical Specification Manual.