AAOM Handbook

INTERNAL

AI.14 Significant Contributing/Root Causes Identified? Context The investigation team ranked the potential causes for a process issue identified during brainstorming from the most to least probable. This was done in the hope of reducing the validation workload by examining the most probable causes first. A method of measuring, testing or modelling the contribution of each probable cause was devised and executed to provide the data necessary to decide whether the significant contributing/root cause(s) have been identified. In the event that a significant contributing/root cause cannot be validated from amongst those that were ranked most probable, the team need to continue the validation process working further down the list of ranked potential causes. If all of the identified potential causes have been tested with data, and no significant contributing/root cause has been identified, the team needs to revisit the brainstorming process to identify more potential causes. Purpose To decide whether the significant contributing/root cause(s) of the process issue have been identified. Quantity One decision whether the validation data has confirmed that the one (or more) of the identified potential cause(s) will substantially deliver the improvement expected in the process. Quality If one, or a few, potential causes account for greater than 50% of the expected benefit identified for the process issue, then these should be identified as significant contributing/root causes. Resources The identification of the significant contributing/root causes is the accountability of the Investigation leader. Time As soon as practical after validation data has been analysed.

© McAlear Management Consultants 2007

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