Root cause analysis (RCA) is a method of problem solving used for identifying the root causes of faults or problems. A factor is considered a root cause if removal thereof from the problem-fault-sequence prevents the final undesirable outcome from recurring; whereas a causal factor is one that affects an event’s outcome, but is not a root cause. Though removing a causal factor can benefit an outcome, it does not prevent its recurrence with certainty.
Essentially it is based on four general principles, extended throughout this
- Define and describe properly the event or problem
- Establish a timeline from normal situation until the final crisis or failure.
- Distinguish between root causes and causal factor.
- Once implemented (and with constant execution), RCA is transformed into a method of problem prediction.
RCA is applied to methodically identify and correct the root causes of events, rather than to simply address the symptomatic result. Focusing correction on root causes has the goal of entirely preventing problem recurrence. Conversely, RCFA (Root Cause Failure Analysis) recognizes that complete prevention of recurrence by one corrective action is not always possible.
RCA is typically used as a reactive method of identifying event causes, revealing problems and solving them. Analysis is done after an event has occurred. Insights in RCA make it potentially useful as a preemptive method. In that event, RCA can be used to forecast or predict probable events even before they occur. While one follows the other, RCA is a completely separate process to incident management.