What is the Protectometer?
The Protectometer is a tool developed by Lorrimer Moseley and David Butler for use by clinicians and patients in helping to understand and manage the causes of an individuals’ experience of pain 
It is one of the tools used in the Explain Pain (EP) approach to pain management developed by Moseley and Butler. This approach uses a number of educational interventions to help patients and clinicians understand and approach the management of pain. 
What are DIMs and SIMs?
DIMs are things that the brain might see as credible evidence of ‘Danger In Me’’. They may be things we hear, see, touch, taste; things we do; things we think and believe; places we go; people in our life; and things happening in our body. 
SIMs are things the brain might see as credible evidence of ‘Safety in Me’. They may be in the same categories as the above. Moseley and Butler propose that ‘You will have pain when your brain concludes that there is more credible evidence of danger in me than there is credible evidence of safety in me’ 
How does this relate to neurophysiology?
DIMs and SIMs are hypothesised by Moseley and Butler to be represented by ‘neurotags’ in the brain. That is, groups of neural networks that evoke outputs from the brain, including pain . This is based somewhat on Melznak’s Neuromatrix theory  They propose that these can be modified and changed, to change the perception of pain, by using the EP approach.
What’s the evidence?
There is growing evidence that the EP approach, which includes the use of The Protectometer and the concepts of DIMS and SIMs, is effective in reducing pain and perceived disability in those with chronic musculoskeletal conditions. 
Research is ongoing, looking at the EP approach when used alone, and as part of a multimodal treatment approach.
- Moseley GL, Butler DS. Explain Pain Supercharged. Adelaide: Noigroup Publications, 2017 p. 15-18
- Moseley GL, Butler DS. The Explain Pain Handbook: Protectometer. Adelaide: Noigroup Publications 2015
- Moseley GL, Butler DS. Explain Pain Supercharged. Adelaide:Noigroup Publications. 2017
- Moseley LG, Butler DS. Fifteen years of Explaining Pain: The Past, Present and Future. J Pain 2015; http://doi.org/10.1016/j.jpain.2015.05.005 (accessed 8 Mar 2018)
- Moseley GL, Butler DS. Explain Pain Supercharged. Adelaide: Noigroup Publications. 2017 pp. 19 -25.
- Melzack R. Phantom limbs and the concept of the neuromatrix. Trends Neurosci 1990; 13: 88-92 cited in Moseley GL, Butler DS. Explain Pain Supercharged. Adelaide: Noigroup Publications. 2017 pp. 19.
- Louw A, Diener I, Butler DS, Puentedura EJ. The effect of neuroscience education on pain, disability, anxiety and stress in Chronic Musculoskeletal Pain. Arch Phys Med Rehabil. 92(12): 2041-2056. http://doi.org.10.1016/j.apmr.2011.07.198 (accessed 9 Mar 2018)
- Butler DS, Moseley LG. Evidence base of Explain Pain Second Edition. Adelaide. Noigroup Publications. 2013. http://www.noigroup.com (accessed 8 March 2018)