title: A modified score to identify and discriminate neuropathic pain: a study on the German version of the Neuropathic Pain Symptom Inventory (NPSI).
abstract: BACKGROUND
  Neuropathic pain must be correctly diagnosed for optimal treatment. The questionnaire named Neuropathic Pain Symptom Inventory (NPSI) was developed in its original French version to evaluate the different symptoms of neuropathic pain. We hypothesized that the NPSI might also be used to differentiate neuropathic from non-neuropathic pain.
  
  
  METHODS
  We translated the NPSI into German using a standard forward-backward translation and administered it in a case-control design to patients with neuropathic (n = 68) and non-neuropathic pain (headache and osteoarthritis, n = 169) to validate it and to analyze its discriminant properties, its sensitivity to change, and to detect neuropathic pain subgroups with distinct profiles.
  
  
  RESULTS
  Using a sum score (the NPSI-G score), we found sensitivity to change (r between 0.37 and 0.5 for pain items of the graded chronic pain scale) and could distinguish between neuropathic and other pain on a group basis, but not for individual patients. Post hoc development of a discriminant score with optimized diagnostic properties to distinguish neuropathic pain from non-neuropathic pain resulted in an instrument with high sensitivity (91%) and acceptable specificity (70%). We detected six different pain profiles in the patient group with neuropathic pain; three profiles were found to be distinct.
  
  
  CONCLUSIONS
  The NPSI-G potentially combines the properties of a diagnostic tool and an instrument to identify subtypes of neuropathic pain.
authors.affiliation: Department of Neurology, University of Würzburg, Germany. sommer@uni-wuerzburg.de.
authors.forename: Claudia
authors.initials: C
authors.lastname: Sommer
authors.forename: Helmut
authors.initials: H
authors.lastname: Richter
authors.forename: Jan P
authors.initials: JP
authors.lastname: Rogausch
authors.forename: Jule
authors.initials: J
authors.lastname: Frettlöh
authors.forename: Margitta
authors.initials: M
authors.lastname: Lungenhausen
authors.forename: Christoph
authors.initials: C
authors.lastname: Maier
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003937:Diagnosis, Differential; D005260:Female; D005858:Germany; D006261:Headache / Q000175:diagnosis; D006801:Humans; D008297:Male; D008875:Middle Aged; D009437:Neuralgia / Q000175:diagnosis*; D010003:Osteoarthritis / Q000150:complications / Q000175:diagnosis; D010146:Pain / Q000150:complications / Q000175:diagnosis; D010147:Pain Measurement / Q000295:instrumentation* / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires