Other tools used in RCA may be process maps or fishbone diagrams, which are helpful in breaking down each step of a system where errors may be introduced.
To use the fishbone diagram, first define the effect (NCE) to the right. Next, brainstorm possible causes that led to the effect based on the categories listed in the "bones" of the chart.
A primary cause would be listed on the top of the line in the "bone" of the diagram; this would be a cause that leads directly to the effect.
A secondary cause would be listed underneath the line in the "bone" of the diagram; it is one that does not directly cause the end effect, but may lead to the primary cause.
