title: Can we "predict" long-term outcome for ambulatory transcutaneous electrical nerve stimulation in patients with chronic pain?
abstract: BACKGROUND
  Evidence for effectiveness of transcutaneous electrical nerve stimulation (TENS) is still inconclusive. As heterogeneity of chronic pain patients might be an important factor for this lack of efficacy, identifying factors for a successful long-term outcome is of great importance.
  
  
  METHODS
  A prospective study was performed to identify variables with potential predictive value for 2 outcome measures on long term (6 months); (1) continuation of TENS, and (2) a minimally clinical important pain reduction of ≥ 33%. At baseline, a set of risk factors including pain-related variables, psychological factors, and disability was measured.
  
  
  RESULTS
  In a multiple logistic regression analysis, higher patient's expectations, neuropathic pain, no severe pain (< 80 mm visual analogue scale [VAS]) were independently related to long-term continuation of TENS. For the outcome "minimally clinical important pain reduction," the multiple logistic regression analysis indicated that no multisited pain (> 2 pain locations) and intermittent pain were positively and independently associated with a minimally clinical important pain reduction of ≥ 33%.
  
  
  CONCLUSIONS
  The results showed that factors associated with a successful outcome in the long term are dependent on definition of successful outcome.
authors.affiliation: Pain Management and Research Center, University Medical Center Maastricht, Maastricht, The Netherlands; Adelante Centre of Expertise in Rehabilitation, Hoensbroek, The Netherlands; Department of Rehabilitation Medicine, Research School CAPHRI, Maastricht University, Maastricht, The Netherlands.
authors.forename: Albère J
authors.initials: AJ
authors.lastname: Köke
authors.forename: Rob J E M
authors.initials: RJ
authors.lastname: Smeets
authors.forename: Roberto S
authors.initials: RS
authors.lastname: Perez
authors.forename: Alphons
authors.initials: A
authors.lastname: Kessels
authors.forename: Bjorn
authors.initials: B
authors.lastname: Winkens
authors.forename: Maarten
authors.initials: M
authors.lastname: van Kleef
authors.forename: Jacob
authors.initials: J
authors.lastname: Patijn
mesh_terms: D000203:Activities of Daily Living; D000223:Adaptation, Psychological; D000328:Adult; D000368:Aged; D058443:Catastrophization; D059350:Chronic Pain / Q000523:psychology / Q000628:therapy*; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D007389:Internal-External Control; D016015:Logistic Models; D017116:Low Back Pain / Q000523:psychology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D019547:Neck Pain / Q000523:psychology / Q000628:therapy*; D009437:Neuralgia / Q000523:psychology / Q000628:therapy*; D010147:Pain Measurement; D011446:Prospective Studies; D012307:Risk Factors; D020377:Self Efficacy; D012720:Severity of Illness Index; D004561:Transcutaneous Electric Nerve Stimulation / Q000379:methods*; D016896:Treatment Outcome; D064232:Visual Analog Scale
keywords: musculoskeletal diseases; outcomes; predictors; transcutaneous electric nerve stimulation