title: Cross-cultural adaptation and validation of a Bengali version of the modified fibromyalgia impact questionnaire.
abstract: BACKGROUND
  Currently, no validated instruments are available to measure the health status of Bangladeshi patients with fibromyalgia (FM). The aims of this study were to cross-culturally adapt the modified Fibromyalgia Impact Questionnaire (FIQ) into Bengali (B-FIQ) and to test its validity and reliability in Bangladeshi patients with FM.
  
  
  METHODS
  The FIQ was translated following cross-cultural adaptation guidelines and pretested in 30 female patients with FM. Next, the adapted B-FIQ was physician-administered to 102 consecutive female FM patients together with the Health Assessment Questionnaire (HAQ), selected subscales of the SF-36, and visual analog scales for current clinical symptoms. A tender point count (TPC) was performed by an experienced rheumatologist. Forty randomly selected patients completed the B-FIQ again after 7 days. Two control groups of 50 healthy people and 50 rheumatoid arthritis (RA) patients also completed the B-FIQ.
  
  
  RESULTS
  For the final B-FIQ, five physical function sub-items were replaced with culturally appropriate equivalents. Internal consistency was adequate for both the 11-item physical function subscale (α = 0.73) and the total scale (α = 0.83). With exception of the physical function subscale, expected correlations were generally observed between the B-FIQ items and selected subscales of the SF-36, HAQ, clinical symptoms, and TPC. The B-FIQ was able to discriminate between FM patients and healthy controls and between FM patients and RA patients. Test-retest reliability was adequate for the physical function subscale (r = 0.86) and individual items (r = 0.73-0.86), except anxiety (r = 0.27) and morning tiredness (r = 0.64).
  
  
  CONCLUSIONS
  This study supports the reliability and validity of the B-FIQ as a measure of functional disability and health status in Bangladeshi women with FM.
authors.affiliation: Rheumatology Wing, Department of Medicine, Bangabandhu Sheikh Mujib, Medical University, Shahbagh, Dhaka, Bangladesh.
authors.forename: Mohammed A
authors.initials: MA
authors.lastname: Muquith
authors.forename: Md Nazrul
authors.initials: MN
authors.lastname: Islam
authors.forename: Syed A
authors.initials: SA
authors.lastname: Haq
authors.forename: Peter M
authors.initials: PM
authors.lastname: Ten Klooster
authors.forename: Johannes J
authors.initials: JJ
authors.lastname: Rasker
authors.forename: Muhammad B
authors.initials: MB
authors.lastname: Yunus
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D001459:Bangladesh / Q000453:epidemiology; D016022:Case-Control Studies; D017281:Cost of Illness; D003466:Cultural Characteristics; D004185:Disability Evaluation; D005260:Female; D005356:Fibromyalgia / Q000175:diagnosis* / Q000208:ethnology; D006304:Health Status; D006801:Humans; D008875:Middle Aged; D010147:Pain Measurement; D011237:Predictive Value of Tests; D011594:Psychometrics; D015203:Reproducibility of Results; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires; D055815:Young Adult