Root cause is a set of circumstances that leads to failure. In the context of ISO/IEC 17025:2017, failure can be considered a nonconformance within the management system or a risk to the laboratory.
ISO/IEC 17025:2017 requires a laboratory to react to nonconformities, evaluate the need for action, and implement action, as needed. In addition, laboratories must plan actions to address risks and opportunities associated with the laboratory’s activities.
While the standard no longer requires a policy or procedure for root cause and corrective action, it is critical for laboratories to understand the need for effective root cause analysis to generate corrective actions that will adequately address the nonconformances, risks, and opportunities identified.
Root cause analysis is used to determine the underlying reason or causes (root cause) of a nonconformance or risk. It can be used to manage risks and improve the management system by identifying corrections and corrective actions to address the underlying issues that allowed the failure to occur in the first place. It is the key to determining corrective actions yielding long-lasting results.
Ineffective root cause analysis yields solutions that act as bandages to the root cause. Often an ineffective root cause analysis will only address the symptoms of a deeper root cause. Effective root cause analysis, on the other hand, will prevent the failure from recurring, leading to permanent changes in the laboratory’s management system.
Many different techniques exist for performing root cause analysis. The most common are the Ishikawa (or fishbone) diagram and five whys. Other techniques include brainstorming, flowcharting, affinity diagrams, Pareto analysis, and failure mode and effects analysis (FMEA). The best technique for performing root cause analysis is one that suites the laboratory and the specific nonconformity or risk being addressed.