title: Determinants of the shoulder pain and disability index in patients with subacromial shoulder pain.
abstract: OBJECTIVE
  To examine the influence of determinants on the Shoulder Pain and Disability Index.
  
  
  METHODS
  A cross-sectional study. Baseline registrations were applied.
  
  
  METHODS
  Two hundred patients with subacromial shoulder pain lasting at least 3 months.
  
  
  METHODS
  A questionnaire consisting of possible determinants, 2 independent variables regarding pain and 2 regarding function, and the outcome measurement. Two multiple regression models (one with and one without the independent variables of pain and function) for the Shoulder Pain and Disability Index, the 2 subscales, and the determinants, were performed.
  
  
  RESULTS
  The included determinants explained 29% of the variance of the Shoulder Pain and Disability Index (25% for pain and 33% for disability subscale) with pain medication, emotional distress, flexion, and the hand-behind-back range accounting for 26%. When pain and function were included, the final model explained 65% of the variance, with gender, education and range of flexion showing significance.
  
  
  CONCLUSIONS
  The determinants explained 26% of the variance of the Shoulder Pain and Disability Index, but explained only a minor proportion when pain and function were included. This supports the Shoulder Pain and Disability Index as a shoulder pain and disability questionnaire.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Oslo University Hospital, Ullevaal, and Medical Faculty, University of Oslo, Oslo, Norway. kaiabe@medisin.uio.no
authors.forename: Kaia
authors.initials: K
authors.lastname: Engebretsen
authors.forename: Margreth
authors.initials: M
authors.lastname: Grotle
authors.forename: Erik
authors.initials: E
authors.lastname: Bautz-Holter
authors.forename: Ole Marius
authors.initials: OM
authors.lastname: Ekeberg
authors.forename: Jens I
authors.initials: JI
authors.lastname: Brox
mesh_terms: D000174:Acromion / Q000503:physiopathology; D000328:Adult; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D004522:Educational Status; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D011379:Prognosis; D016059:Range of Motion, Articular; D020069:Shoulder Pain / Q000175:diagnosis* / Q000503:physiopathology / Q000534:rehabilitation; D011795:Surveys and Questionnaires