title: Comparison of surveys used to measure physical activity.
abstract: OBJECTIVE
  To compare the level of agreement in results obtained from four physical activity (PA) measurement instruments that are in use in Australia and around the world.
  
  
  METHODS
  1,280 randomly selected participants answered two sets of PA questions by telephone. 428 answered the Active Australia (AA) and National Health Surveys, 427 answered the AA and CDC Behavioural Risk Factor Surveillance System surveys (BRFSS), and 425 answered the AA survey and the short International Physical Activity Questionnaire (IPAQ).
  
  
  RESULTS
  Among the three pairs of survey items, the difference in mean total PA time was lowest when the AA and NHS items were asked (difference=24) (SE:17) minutes, compared with 144 (SE:21) mins for AA/BRFSS and 406 (SE:27) mins for AA/IPAQ). Correspondingly, prevalence estimates for 'sufficiently active' were similar for AA and NHS (56% and 55% respectively), but about 10% higher when BRFSS data were used, and about 26% higher when the IPAQ items were used, compared with estimates from the AA survey.
  
  
  CONCLUSIONS
  The findings clearly demonstrate that there are large differences in reported PA times and hence in prevalence estimates of 'sufficient activity' from these four measures.
  
  
  CONCLUSIONS
  It is important to consistently use the same survey for population monitoring purposes. As the AA survey has now been used three times in national surveys, its continued use for population surveys is recommended so that trend data over a longer period of time can be established.
authors.affiliation: School of Human Movement Studies, University of Queensland, St Lucia. wbrown@hms.uq.edu.au
authors.forename: Wendy
authors.initials: W
authors.lastname: Brown
authors.forename: Adrian
authors.initials: A
authors.lastname: Bauman
authors.forename: Tien
authors.initials: T
authors.lastname: Chey
authors.forename: Stewart
authors.initials: S
authors.lastname: Trost
authors.forename: Kerry
authors.initials: K
authors.lastname: Mummery
mesh_terms: D003625:Data Collection; D015444:Exercise; D006801:Humans; D011793:Queensland