2.2.4. Revised Neurophysiology Pain Questionnaire (R-NPQ)

The Neurophysiology of Pain Questionnaire (NPQ) was initially developed by Moseley et al. [46] to assess postgraduate medical students’ understanding of the biology of pain. The language of the original NPQ has been adapted for patients and is used both in clinical practice and in research [47,48,49,50]. The original 19-item questionnaire was revised by conducting a Rasch analysis: acceptable internal consistency (person separation index = 0.84) and test–retest reliability were reported (ICC = 0.97) in patients with chronic pain, but Seven items were found to have suboptimal functionality, thus adversely affecting the psychometric properties [40]. This revised version (R-NPQ) is a valid and reliable tool for assessing the neurophysiology of pain. Each item has a true, false or undecided response; correct responses were given 1 point, and incorrect (or undecided) responses were given 0 points. Therefore, the result is determined by adding up the number of correct answers, and the overall score can range from 0 to 12, with higher scores indicating greater knowledge about pain.

Our study utilised the Spanish version of the R-NPQ [51], which had already been translated and cross-culturally adapted for use with patients and PTs. This version demonstrated satisfactory psychometric properties (Cronbach’s alpha = 0.90; ICC = 0.82).