title: A biopsychosocial model of disability in rheumatoid arthritis.
abstract: OBJECTIVE
  To test and cross-validate a model using disease activity, pain, and helplessness to predict future psychological and physical disability in persons with rheumatoid arthritis (RA) across time.
  
  
  METHODS
  Measures of disease activity, pain, helplessness, psychological function, and physical function were collected from 63 males with RA at baseline, 3 months, and 6 months. Path analytic methods were used to examine longitudinal relationships among these variables.
  
  
  RESULTS
  Path analysis revealed that pain and helplessness were significant mediators of the relationship between disease activity and future disability in RA; the predictive model withstood two cross-validations.
  
  
  CONCLUSIONS
  The findings suggest that pain and helplessness are key biopsychosocial variables that affect the development of disability in RA.
authors.affiliation: Harry S Truman Memorial Veterans Hospital, Columbia, MO 65201, USA.
authors.forename: K
authors.initials: K
authors.lastname: Schoenfeld-Smith
authors.forename: G F
authors.initials: GF
authors.lastname: Petroski
authors.forename: J E
authors.initials: JE
authors.lastname: Hewett
authors.forename: J C
authors.initials: JC
authors.lastname: Johnson
authors.forename: G E
authors.initials: GE
authors.lastname: Wright
authors.forename: K L
authors.initials: KL
authors.lastname: Smarr
authors.forename: S E
authors.initials: SE
authors.lastname: Walker
authors.forename: J C
authors.initials: JC
authors.lastname: Parker
mesh_terms: D000203:Activities of Daily Living; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000503:physiopathology / Q000523:psychology; D006233:Persons with Disabilities; D005163:Factor Analysis, Statistical; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D011237:Predictive Value of Tests; D013997:Time Factors