title: Waddell's symptoms as correlates of vulnerabilities associated with fear-anxiety-avoidance models of pain: pain-related anxiety, catastrophic thinking, perceived disability, and treatment outcome.
abstract: BACKGROUND
  Fear-anxiety-avoidance models of chronic pain emphasize psychological constructs as key vulnerabilities for the development and maintenance of disabling chronic pain. Complementarily, Waddell described physical signs and symptoms thought inconsistent with anatomic and pathologic disease patterns that might function as indications of pain-related psychological distress. Research has not supported using Waddell's signs due to low inter-rater reliability and limited associations with psychological distress; however, these findings are equivocal. Similarly, theorists have suggested that endorsement of Waddell's symptoms may indicate psychological distress; however, the precedent research has not included the psychological constructs described in fear-anxiety-avoidance models as vulnerability factors for the development and maintenance of chronic pain.
  
  
  METHODS
  Participants for the current study were patients (n = 68; 35% women) with chronic low back pain involved in a multi-disciplinary work-hardening program provided by a third-party insurer. Patients endorsing more than two of Waddell's symptoms were compared with those who did not on demographic variables as well as established self-report psychological measures, measures of perceived disability, functional capacity, and treatment outcome.
  
  
  RESULTS
  Patients endorsing more than two of Waddell's symptoms reported higher levels of depressive symptoms, pain-related anxiety, fear, catastrophizing, and pain intensity. Unexpectedly, there were no significant differences in functional capacity. Similar differences were found between those who did and did not return to work.
  
  
  CONCLUSIONS
  While Waddell's symptoms must still be interpreted judiciously, they may provide much needed cross-disciplinary utility as indicators that more detailed psychological assessment is warranted. Comprehensive implications and directions for future research are discussed.
authors.affiliation: Anxiety and Illness Behaviours Laboratory, University of Regina, Regina, SK S4S 0A2, Canada. carletor@uregina.ca
authors.forename: R N
authors.initials: RN
authors.lastname: Carleton
authors.forename: M P
authors.initials: MP
authors.lastname: Abrams
authors.forename: S S
authors.initials: SS
authors.lastname: Kachur
authors.forename: G J G
authors.initials: GJ
authors.lastname: Asmundson
mesh_terms: D000062:Accidents, Occupational; D000328:Adult; D001007:Anxiety; D002908:Chronic Disease / Q000523:psychology*; D004185:Disability Evaluation; D005239:Fear; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000523:psychology*; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D012649:Self Concept; D012803:Sick Role; D013315:Stress, Psychological; D055815:Young Adult