title: Patient self-report section of the ASES questionnaire: a Spanish validation study using classical test theory and the Rasch model.
abstract: BACKGROUND
  The aim of the current study was to validate the self-report section of the American Shoulder and Elbow Surgeons questionnaire (ASES-p) into Spanish.
  
  
  METHODS
  Shoulder pathology patients were recruited and followed up to 6 months post treatment. The ASES-p, Constant, SF-36 and Barthel scales were filled-in pre and post treatment. Reliability was tested with Cronbach's alpha, convergent validity with Spearman's correlations coefficients. Confirmatory factor analysis (CFA) and the Rasch model were implemented for assessing structural validity and unidimensionality of the scale. Models with and without the pain item were considered. Responsiveness to change was explored via standardised effect sizes.
  
  
  RESULTS
  Results were acceptable for both tested models. Cronbach's alpha was 0.91, total scale correlations with Constant and physical SF-36 dimensions were >0.50. Factor loadings for CFA were >0.40. The Rasch model confirmed unidimensionality of the scale, even though item 10 "do usual sport" was suggested as non-informative. Finally, patients with improved post treatment shoulder function and those receiving surgery had higher standardised effect sizes.
  
  
  CONCLUSIONS
  The adapted Spanish ASES-p version is a valid and reliable tool for shoulder evaluation and its unidimensionality is supported by the data.
authors.affiliation: Unidad de Investigación de Atención Primaria-OSIS de Gipuzkoa, Instituto Biodonostia, Paseo Dr. Begiristain s/n, 20014, San Sebastián, Spain. KALLIOPI.VROTSOUKANARI@osakidetza.net.|Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Bilbao, Spain. KALLIOPI.VROTSOUKANARI@osakidetza.net.|Instituto de Investigación Sanitaria Biodonostia, San Sebastián, Spain. KALLIOPI.VROTSOUKANARI@osakidetza.net.
authors.forename: Kalliopi
authors.initials: K
authors.lastname: Vrotsou
authors.affiliation: Servicio de Traumatología y Cirugía Ortopédica, Hospital Universitario Donostia, San Sebastián, Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Cuéllar
authors.affiliation: Servicio de Traumatología y Cirugía Ortopédica, Hospital Universitario Basurto, Bilbao, Spain.
authors.forename: Félix
authors.initials: F
authors.lastname: Silió
authors.affiliation: Servicio de Traumatología y Cirugía Ortopédica, Hospital Universitario Cruces, Barakaldo, Spain.
authors.forename: Miguel Ángel
authors.initials: MÁ
authors.lastname: Rodriguez
authors.affiliation: Servicio de Traumatología y Cirugía Ortopédica, Hospital Galdakao-Usansolo, Galdakao, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Garay
authors.affiliation: Servicio de Traumatología y Cirugía Ortopédica, Hospital de Mendaro, Mendaro, Spain.
authors.forename: Gorka
authors.initials: G
authors.lastname: Busto
authors.affiliation: Unidad de Investigación, Hospital Universitario Basurto, Bilbao, Spain.
authors.forename: Ziortza
authors.initials: Z
authors.lastname: Trancho
authors.affiliation: Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Bilbao, Spain.|Unidad de Investigación, Hospital Universitario Basurto, Bilbao, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Escobar
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005163:Factor Analysis, Statistical; D005260:Female; D006630:Hispanic or Latino / Q000523:psychology; D006801:Humans; D007802:Language; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D015203:Reproducibility of Results; D057566:Self Report; D012782:Shoulder / Q000503:physiopathology; D020069:Shoulder Pain / Q000208:ethnology* / Q000209:etiology* / Q000523:psychology; D011795:Surveys and Questionnaires; D014177:Translations; D055815:Young Adult
keywords: ASES-p; Confirmatory factor analysis; Constant Murley Score; Rasch model; Responsiveness; SF-36; Shoulder; Spanish validation; Validity