Combat Stress Reaction - PIE Principles

PIE Principles

The PIE principles were in place for the "not yet diagnosed nervous" (NYDN) cases:

• Proximity – treat the casualties close to the front and within sound of the fighting
• Immediacy – treat them without delay and not wait until the wounded were all dealt with
• Expectancy – ensure that everyone had the expectation of their return to the front after a rest and replenishment

United States medical officer Thomas W. Salmon is often quoted as the originator of these PIE principles. However, his real strength came from going to Europe and learning from the Allies and then instituting the lessons. By the end of the war, Salmon had set up a complete system of units and procedures that was then the "world’s best practice". After the war he maintained his efforts in educating society and the military. He was awarded the Distinguished Service Medal for his contributions.

The effectiveness of the PIE approach has not been confirmed by studies of CSR, and there is some evidence that it is not effective in preventing PTSD.

The US services now use the more recently developed BICEPS principles:

• Brevity
• Immediacy
• Centrality or Contact
• Expectancy
• Proximity
• Simplicity