title: Cross-cultural adaptation and validation of the VISA-P questionnaire for German-speaking patients with patellar tendinopathy.
abstract: METHODS
  Clinical measurement study.
  
  
  OBJECTIVE
  To cross-culturally adapt and validate the Victorian Institute of Sports Assessment Patellar Tendinopathy Questionnaire (VISA-P) for German-speaking patients.
  
  
  BACKGROUND
  Like most questionnaires, the VISA-P was developed for English-speaking patients. There is a need to adapt the scale for German-speaking patients and thereby add to the total body of psychometric evidence relating to this instrument.
  
  
  METHODS
  The VISA-P questionnaire was translated and cross-culturally adapted into German (VISA-P-G) in 6 steps: translation, synthesis, back translation, expert committee review, pretesting, and advisory committee appraisal. The psychometric properties of the VISA-P-G were determined using 23 patients with patellar tendinopathy and 57 active healthy persons (32 sport students and 25 basketball players). Reliability was evaluated by applying the questionnaire twice within a week to all 80 participants. Known group validity was calculated using a 1-way analysis of variance. Additionally, VISA-P-G results were correlated with the Blazina classification system for patellar tendinopathy, using the Spearman rank correlation coefficient. VISA-P-G ratings from the present study groups were further compared with respective data published in the original English, Dutch, and Swedish versions by a 2-sample t test. Internal consistency for the individual items of the questionnaire was determined within the patient group using a Cronbach alpha.
  
  
  RESULTS
  Test-retest revealed excellent reliability for the patient and the asymptomatic control group (ICC = 0.88 and 0.87, respectively). Internal consistency for the patients was 0.88. Concurrent validity was almost perfect (ρ = -0.81; P<.001).
  
  
  CONCLUSIONS
  The VISA-P-G is a reliable and valid questionnaire for the self-assessment of pain, symptoms, and function in German-speaking patients with patellar tendinopathy. Its psychometric properties are comparable with the original English and international adaptations (Swedish, Dutch, and Italian).
authors.affiliation: Institute for Sports Medicine, Frankfurt, Germany. lohrer@smi-frankfurt.de
authors.forename: Heinz
authors.initials: H
authors.lastname: Lohrer
authors.forename: Tanja
authors.initials: T
authors.lastname: Nauck
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001265:Athletic Injuries / Q000175:diagnosis* / Q000503:physiopathology; D003466:Cultural Characteristics; D005260:Female; D005858:Germany; D006801:Humans; D007802:Language; D008297:Male; D010329:Patella / Q000503:physiopathology*; D011237:Predictive Value of Tests; D011594:Psychometrics; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D052256:Tendinopathy / Q000175:diagnosis* / Q000503:physiopathology; D014177:Translations