title: People with low back pain who have externalised beliefs need to see greater improvements in symptoms to consider exercises worthwhile: an observational study.
abstract: OBJECTIVE
  Does health locus of control predict the smallest worthwhile effect of motor control exercise or spinal manipulative therapy when adjusted for severity of pain?
  
  
  METHODS
  Cross-sectional observational study.
  
  
  METHODS
  86 people with non-specific low back pain who had not yet commenced physiotherapy intervention.
  
  
  METHODS
  Predictors were severity of pain measured over the last 7 days using an 11-point scale from 0 to 10, and external and internal health loci of control measured using Form C of the Multidimensional Health Locus of Control scale. The outcome of interest was smallest worthwhile effect which was measured in terms of the percentage perceived change necessary to make two evidence-based physiotherapy interventions for non-specific low back pain (motor control exercise and spinal manipulative therapy) worthwhile. Data were collected before intervention commenced.
  
  
  RESULTS
  Multivariate analysis showed that when adjusted for pain and internal locus of control, external locus of control predicted the smallest worthwhile effect for motor control exercise (B 0.79; CI 0.10 to 1.48), explaining 0.07 of the variance. None of the predictors significantly predicted the smallest worthwhile effect for spinal manipulative therapy.
  
  
  CONCLUSIONS
  Patients with low back pain who have externalised beliefs and agree more strongly with the notion that others are responsible for their condition report higher estimates of smallest worthwhile effect of an active intervention such as motor control exercise than patients who do not have externalised beliefs.
authors.affiliation: Universidade Federal de Minas Gerais, Brazil.
authors.forename: Vinicius Cunha
authors.initials: VC
authors.lastname: Oliveira
authors.forename: Paulo H
authors.initials: PH
authors.lastname: Ferreira
authors.forename: Manuela L
authors.initials: ML
authors.lastname: Ferreira
authors.forename: Leticia
authors.initials: L
authors.lastname: Tiburcio
authors.forename: Rafael Zambelli
authors.initials: RZ
authors.lastname: Pinto
authors.forename: Warley
authors.initials: W
authors.lastname: Oliveira
authors.forename: Rosangela
authors.initials: R
authors.lastname: Dias
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005081:Exercise Therapy / Q000523:psychology*; D005260:Female; D019538:Health Care Surveys; D006801:Humans; D017116:Low Back Pain / Q000523:psychology* / Q000534:rehabilitation*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017063:Outcome Assessment, Health Care; D010342:Patient Acceptance of Health Care; D011237:Predictive Value of Tests; D012649:Self Concept; D012720:Severity of Illness Index; D016896:Treatment Outcome