title: Test-retest repeatability and relative validity of the Global Physical Activity Questionnaire in a developing country context.
abstract: BACKGROUND
  The increasing prevalence of chronic lifestyle diseases in developing countries warrants reliable and valid surveillance of physical activity levels in the population. This study assesses the test-retest repeatability and criterion validity of the WHO-recommended Global Physical Activity Questionnaire (GPAQ) in Vietnamese adults during the dry and wet seasons.
  
  
  METHODS
  In 2007 a representative sample of 169 adults (25-64 years) was recruited to determine the GPAQ reliability and validity. GPAQ assesses time and intensity of physical activities spent during a usual week. To assess short and long term reliability, participants completed the GPAQ twice during the dry season 2 weeks apart and again 2 months later during the wet season. For validation purposes, participants wore an accelerometer during the 7 days before the first and last GPAQ assessments.
  
  
  RESULTS
  The total GPAQ score showed repeatability correlations of 0.69 after 2 weeks and of 0.55 after 2 months. Total GPAQ score and accelerometer data showed validity correlations of 0.34 and 0.20 in the dry and wet season, respectively. There was a difference in physical activity patterns between the dry and wet seasons.
  
  
  CONCLUSIONS
  GPAQ is suitable for surveillance of physical activity among adults in Vietnam.
authors.affiliation: Centre for Physical Activity and Health, University of Sydney, Australia.
authors.forename: Oanh T H
authors.initials: OT
authors.lastname: Trinh
authors.forename: Nguyen Do
authors.initials: ND
authors.lastname: Nguyen
authors.forename: Hidde P
authors.initials: HP
authors.lastname: van der Ploeg
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Dibley
authors.forename: Adrian
authors.initials: A
authors.lastname: Bauman
mesh_terms: D056044:Actigraphy; D000328:Adult; D015444:Exercise; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012621:Seasons; D011795:Surveys and Questionnaires; D014744:Vietnam