The methods used during preventive and corrective actions are very similar. However, it is important to understand the differences between them and and be aware of the implications involved when capturing information for each.
A corrective action is a reaction to a problem that has already occurred and been reported by either external or internal sources.
A preventive action is initiated to stop a potential problem from occurring at all. Preventive actions usually rely on adequate monitoring controls that are in place as part of the QMS. In other words, if something in the QMS indicates a possible problem may develop, a preventive action may be implemented to avert a negative situation.