title: Reliability and validity study of Persian modified version of MUSIC (musculoskeletal intervention center) - Norrtalje questionnaire.
abstract: BACKGROUND
  Musculoskeletal disorders (MSDs) are a major health problem in the world. Self-reported questionnaires are a known method for estimating the prevalence of MSDs among the population. One of the studies concerning MSDs and their relation to work-related physical and psychosocial factors, as well as non-work-related factors, is the MUSIC-Norrtalje study in Sweden. In this study, the research group developed a questionnaire, which has been validated during its development process and is now considered a well-known instrument. The aim of this study is to validate the Persian version of this questionnaire.
  
  
  METHODS
  The first step was to establish two expert panel groups in Iran and Sweden. The Focus Group Discussion (FGD) method was used to detect questionnaire face and content validity. To detect questionnaire reliability, we used the test-retest method.
  
  
  RESULTS
  Except for two items, all other questions that respondents had problems with in the focus group (20 of 297), had unclear translations; the ambiguity was related to the stem of the questions and the predicted answers were clear for the participants. The concepts of 'household/spare time' and 'physical activity in the workplace' were not understood by the participants of FGD; this has been solved by adding further descriptions to these phrases in the translation. In the test-retest study, the reliability coefficient was relatively high in most items (only 5 items out of 297 had an ICC or kappa below 0.7).
  
  
  CONCLUSIONS
  The findings from the present study provide evidence that the Persian version of the MUSIC questionnaire is a reliable and valid instrument.
authors.affiliation: Department of Clinical Neuroscience, Section for Personal Injury, Karolinska Institutet, Sweden. akbar.alipour@ki.se
authors.forename: Akbar
authors.initials: A
authors.lastname: Alipour
authors.forename: Mostafa
authors.initials: M
authors.lastname: Ghaffari
authors.forename: Irene
authors.initials: I
authors.lastname: Jensen
authors.forename: Batoul
authors.initials: B
authors.lastname: Shariati
authors.forename: Eva
authors.initials: E
authors.lastname: Vingard
mesh_terms: D017144:Focus Groups; D006801:Humans; D007492:Iran / Q000453:epidemiology; D009140:Musculoskeletal Diseases / Q000453:epidemiology* / Q000523:psychology*; D009784:Occupational Diseases / Q000453:epidemiology / Q000523:psychology; D015995:Prevalence; D011584:Psychology; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*; D017132:Workplace / Q000706:statistics & numerical data