Research recommendation(s) from an individual piece of guidance Guidance: Percutaneous electrical nerve stimulation for refractory neuropathic pain Date issued: 27 March 2013 Research recommendations coming out of this guidance NICE encourages further research into percutaneous electrical nerve stimulation (PENS) for refractory neuropathic pain, particularly to provide more information about selection criteria and long-term outcomes, with clear documentation of the indications for treatment.