title: Psychometric evaluation of a Brazilian version of the impact of weight on quality of life (IWQOL-Lite) instrument.
abstract: OBJECTIVE
  The impact of weight on quality of life (IWQOL-Lite) is a self-administered instrument that assesses quality of life in obesity. It is composed of 31 items and five domains (physical function, self-esteem, sexual life, public distress, and work). The aim of the present study was to evaluate reliability (test-retest), internal structure, construct validity and discriminant validity.
  
  
  METHODS
  IWQOL-Lite scores were obtained from 89 people in a Weight Watchers institution (clinical sample) and 156 community volunteers (community sample). The participants were selected based on the same criteria: gender (female) and age (> 24 years), except for BMI. The community sample also completed the SF-36, a generic measure of health-related quality of life.
  
  
  RESULTS
  The Brazilian IWQOL-Lite demonstrated good test-retest reliability, internal consistency, discriminative validity and convergent validity.
  
  
  CONCLUSIONS
  The IWQOL-Lite is the first specific instrument validated in Brazil for assessing quality of life in obesity. The results reveal that IWQOL-Lite is an instrument with good psychometric properties. Nevertheless, in some cases results were dissimilar to those reported in earlier studies using the original American English.
authors.affiliation: Health Sciences and Biomedicine Pernambuco State University, Rheumatologist Oswaldo Cruz University Hospital of the State University of Pernambuco, Brazil. mhz@hotlink.com.br
authors.forename: M H
authors.initials: MH
authors.lastname: de A Mariano
authors.forename: R L
authors.initials: RL
authors.lastname: Kolotkin
authors.forename: K
authors.initials: K
authors.lastname: Petribú
authors.forename: M
authors.initials: M
authors.lastname: de N L Ferreira
authors.forename: R F
authors.initials: RF
authors.lastname: Dutra
authors.forename: M V G
authors.initials: MV
authors.lastname: Barros
authors.forename: N C
authors.initials: NC
authors.lastname: Almeida
authors.forename: L E
authors.initials: LE
authors.lastname: de L Filho
authors.forename: P J
authors.initials: PJ
authors.lastname: Rabelo
authors.forename: V
authors.initials: V
authors.lastname: Monteiro
authors.forename: B F
authors.initials: BF
authors.lastname: da Silva
mesh_terms: D000328:Adult; D001938:Brazil; D003430:Cross-Sectional Studies; D005260:Female; D006304:Health Status; D006306:Health Surveys; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000523:psychology*; D018579:Patient Selection; D011594:Psychometrics / Q000592:standards*; D011788:Quality of Life / Q000523:psychology*; D015203:Reproducibility of Results; D012649:Self Concept; D011795:Surveys and Questionnaires / Q000592:standards*