Once the problem has been described and the potential causes identified, the team should be evaluated. Are the right members on the team to investigate the potential causes? Are technical advisors required to assist in any special studies? Do new team members need to be added? Is the authority to pursue the analysis of the potential causes well defined? All these questions must be answered to ensure the team will be successful in investigating the potential causes and determining the root cause.
The cause and effect diagram is used to identify the potential causes to be investigated. What is the probability that a potential cause could be responsible for the problem? Identify all potential causes that could have been present and may have caused the problem.
Once all potential causes have been agreed upon, choose several potential causes to investigate. If only one potential cause is investigated, a lot of time may be lost if that potential cause proves not to be the culprit. To expedite a solution, investigate several potential causes at the same time (Parallel actions on several potential causes).
. 
