title: Determination of moderate-to-severe postoperative pain on the numeric rating scale: a cut-off point analysis applying four different methods.
abstract: BACKGROUND
  Cut-off points (CPs) of the numeric rating scale (NRS 0-10) are regularly used in postoperative pain treatment. However, there is insufficient evidence to identify the optimal CP between mild and moderate pain.
  
  
  METHODS
  A total of 435 patients undergoing general, trauma, or oral and maxillofacial surgery were studied. To determine the optimal CP for pain treatment, four approaches were used: first, patients estimated their tolerable postoperative pain intensity before operation; secondly, 24 h after surgery, they indicated if they would have preferred to receive more analgesics; thirdly, satisfaction with pain treatment was analysed, and fourthly, multivariate analysis was used to calculate the optimal CP for pain intensities in relation to pain-related interference with movement, breathing, sleep, and mood.
  
  
  RESULTS
  The estimated tolerable postoperative pain before operation was median (range) NRS 4.0 (0-10). Patients who would have liked more analgesics reported significantly higher average pain since surgery [median NRS 5.0 (0-9)] compared with those without this request [NRS 3.0 (0-8)]. Patients satisfied with pain treatment reported an average pain intensity of median NRS 3.0 (0-8) compared with less satisfied patients with NRS 5.0 (2-9). Analysis of average postoperative pain in relation to pain-related interference with mood and activity indicated pain categories of NRS 0-2, mild; 3-4, moderate; and 5-10, severe pain.
  
  
  CONCLUSIONS
  Three of the four methods identified a treatment threshold of average pain of NRS≥4. This was considered to identify patients with pain of moderate-to-severe intensity. This cut-off was indentified as the tolerable pain threshold.
authors: Department of Anaesthesiology and Intensive Care, University Medical Centre Utrecht, Heidelberglaan 100, 3584 GA Utrecht, The Netherlands. h.j.gerbershagen@umcutrecht.nl
authors: H J
authors: HJ
authors: Gerbershagen
authors: J
authors: J
authors: Rothaug
authors: C J
authors: CJ
authors: Kalkman
authors: W
authors: W
authors: Meissner
mesh_terms: D000293:Adolescent; D000328:Adult; D000339:Affect / Q000502:physiology; D000368:Aged; D000700:Analgesics / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000379:methods*; D017288:Pain Threshold / Q000502:physiology; D010149:Postoperative Pain / Q000175:diagnosis* / Q000188:drug therapy; D017060:Patient Satisfaction; D012015:Reference Standards; D012119:Respiration; D012890:Sleep / Q000502:physiology; D011795:Surveys and Questionnaires; D020711:Threshold Limit Values; D055815:Young Adult
chemical_list: D000700:Analgesics