Causal Factor

A causal factor is a condition or action that did (or can) affect an entity by causing, contributing, influencing, or permitting a change to that entity. In other words, it is a factor that is causal to a change. Example: there is an unlit candle in a holder on the table. You strike a match, […]

Causal Factor Tree Analysis

Description Causal factor tree analysis is a Root Cause Analysis technique used to record and display, in a logical, tree-structured hierarchy, all the actions and conditions (or Causal Factors) that were Necessary and Sufficient for a given consequence to have occurred. Pros and Cons Pros Provides structure for the recording of evidence and display of […]

Top 5 Reasons for Failed Root Cause Analysis

Root cause analysis is one of the best ways to solve difficult or significant problems, but sometimes, root cause analysis efforts fail because the corrective actions weren’t effective. If the original problem happens again, or the needed improvements haven’t materialized, or a new problem arises because of the corrective actions, you need to figure out what happened […]

RCA Article Guide

There’s a large number of root cause analysis articles on this site. If you’re already a cause analysis pro, then you can probably just pick through the main RCA Articles list and find things that might interest you. However, if you’re new to root cause analysis, then that probably isn’t going to be a great way to […]

Evaluating the Quality of a Root Cause Analysis

The quality of a Root Cause Analysis (RCA) and its Corrective Action Plan (CAP) should be evaluated many times over its lifecycle (i.e., from initial problem or event, through to final verified and sustainable improved state). Reviews occurring earlier in the lifecycle can really consider only the apparent quality of the investigation/analysis effort itself; these early reviews […]

Recent Changes

Recent changes to this Root Cause Analysis wiki are logged below. 2014-10-04 :: topic pages Barrier and Root Cause created 2014-10-02 :: topic pages Event and Problem created 2014-10-01 :: topic pages Causal Factor and Necessary and Sufficient created  


  In the practice of Root Cause Analysis, a problem is a state that occurs when there is an apparently uncorrectable mismatch between what exists and what is required or desired. In other words, we want w but we have h, and we don’t know how to close the gap. This state can arise in several ways. At […]

Necessary and Sufficient

  Causes and Causal Factors can usually be characterized as having two distinct but related qualities, termed Necessary and Sufficient. Necessary: If x is required for y to occur, then y cannot occur unless x is present; x is a necessary cause of y. If evidence that y occurred is found, then x must have […]

RCA Wiki

  This page is the root for the new Root Cause Analysis wiki. Only the topic pages listed below have been completed. As more pages are created, some kind of directory will be added. The latest changes will be logged to Recent Changes. Barrier Causal Factor Event Necessary and Sufficient Problem Root Cause