Pain after spinal cord injury: an evidence-based review for clinical practice and research. Report of the National Institute on Disability and Rehabilitation Research Spinal Cord Injury Measures meeting.

Background/objectives: To examine the reliability, validity, sensitivity, and practicality of various outcome measures for pain after spinal cord injury (SCI), and to provide recommendations for specific measures for use in clinical trials.

Data Sources: Relevant articles were obtained through a search of MEDLINE, EMBASE, CINAHL, and PubMed databases from inception through 2006.

Study Selection: The authors performed literature searches to find articles containing data relevant to the reliability and validity of each pain outcome measure in SCI and selected non-SCI populations.

Data Extraction: After reviewing the articles, an investigator extracted information utilizing a standard template. A second investigator reviewed the chosen articles and the extracted pertinent information to confirm the findings of the first investigator.

Data Synthesis: Taking into consideration both the quantity and quality of the studies analyzed, judgments on reliability and validity of the measures were made by the two investigators. Based upon these judgments, recommendations were formulated for use of specific measures in future clinical trials. In addition, for a subset of measures a voting process by a larger group of SCI experts allowed formulation of recommendations including determining which measures should be incorporated into a minimal dataset of measures for clinical trials and which ones need revision and further validity and reliability testing before use.

Conclusions: A 0-10 Point Numerical Rating Scale (NRS) is recommended as the outcome measure for pain intensity after SCI, while the 7-Point Guy/Farrar Patient Global Impression of Change (PGIC) scale is recommended as the outcome measure for global improvement in pain. The SF-36 single pain interference question and the Multidimensional Pain Inventory (MPI) or Brief Pain Inventory (BPI) pain interference items are recommended as the outcome measures for pain interference after SCI. Brush or cotton wool and at least one high-threshold von Frey filament are recommended to test mechanical allodynia/hyperalgesia while a Peltier-type thermotester is recommended to test thermal allodynia/hyperalgesia. The International Association for the Study of Pain (IASP) or Bryce-Ragnarsson pain taxonomies are recommended for classification of pain after SCI, while the Neuropathic Pain Scale (NPS) is recommended for measuring change in neuropathic pain and the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) for quantitating neuropathic and nociceptive pain discrimination.