title: Differing Psychologically Derived Clusters in People With Chronic Low Back Pain are Associated With Different Multidimensional Profiles.
abstract: To explore the existence of subgroups in a cohort with chronic low back pain (n=294) based upon data from multiple psychological questionnaires, and profile subgroups on data from multiple dimensions.
  
  
  
  Psychological questionnaires considered as indicator variables entered into latent class analysis included: Depression, Anxiety, Stress scales, Thought Suppression and Behavioural Endurance subscales (Avoidance Endurance questionnaire), Chronic Pain Acceptance Questionnaire (short-form), Pain Catastrophising Scale, Pain Self-Efficacy Questionnaire, and Fear-Avoidance Beliefs Questionnaire. Multidimensional profiling of derived clusters included: demographics, pain characteristics, pain responses to movement, behaviors associated with pain, body perception, pain sensitivity, and health and lifestyle factors.
  
  
  
  Three clusters were derived. Cluster 1 (23.5%) was characterized by low Cognitive and Affective Questionnaire scores, with the exception of fear-avoidance beliefs. Cluster 2 (58.8%) was characterized by relatively elevated thought suppression, catastrophizing, and fear-avoidance beliefs, but lower pain self-efficacy, depression, anxiety, and stress. Cluster 3 (17.7%) had the highest scores across cognitive and affective questionnaires.Cluster 1 reported significantly lower pain intensity and bothersomeness than other clusters. Disability, stressful life events, and low back region perceptual distortion increased progressively from cluster 1 to cluster 3, whereas mindfulness progressively decreased. Clusters 2 and 3 had more people with an increase in pain following repeated forward and backward spinal bending, and more people with increasing pain following bending, than cluster 1. Cluster 3 had significantly greater lumbar pressure pain sensitivity, more undiagnosed comorbid symptoms, and more widespread pain than other clusters.
  
  
  
  Clinical implications relating to presentations of each cluster are postulated.
authors.affiliation: School of Physiotherapy and Exercise Science, Curtin University of Technology, Perth, WA, Australia.
authors.forename: Martin
authors.initials: M
authors.lastname: Rabey
authors.forename: Anne
authors.initials: A
authors.lastname: Smith
authors.forename: Darren
authors.initials: D
authors.lastname: Beales
authors.forename: Helen
authors.initials: H
authors.lastname: Slater
authors.forename: Peter
authors.initials: P
authors.lastname: O'Sullivan
mesh_terms: D000223:Adaptation, Psychological; D001007:Anxiety; D001362:Avoidance Learning; D058443:Catastrophization; D003430:Cross-Sectional Studies; D003863:Depression; D004185:Disability Evaluation; D005239:Fear; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000175:diagnosis* / Q000523:psychology*; D008297:Male; D008875:Middle Aged; D011581:Psychological Tests; D055500:Resilience, Psychological; D020377:Self Efficacy; D013315:Stress, Psychological; D011795:Surveys and Questionnaires