The validity and reliability of an instrument to assess children's outdoor play in various locations.

The aim of this study was to develop and test the reliability and validity of survey items that examine the frequency with which primary school-aged children play in particular outdoor locations. Parents reported the number of days their child spent playing in specified outdoor locations (i.e., yard at home, own street/court/footpath, and park/playground) out-of-school hours on weekdays and weekend days during a typical week. To test the reliability of these items, the survey was administered on two occasions, 2 weeks apart, to a sample of 53 parents of children attending primary schools located in metropolitan Melbourne. The validity study involved the completion of a log book by 46 parents of primary school children over a 1-week period. Two weeks later, the same sample of parents completed the survey items. The test-retest reliability of individual items was determined using intra-class correlation coefficients (ICC). The kappa statistic and percent agreement between responses were used to assess validity by comparing the information provided in the log book with that provided in the survey. Results from the two studies suggest that the survey was generally a reliable and valid instrument for assessing the frequency with which children play in particular locations especially at home or in the street. Evidence of the reliability and validity of items assessing where children play is novel and important considering the need to promote children's physical activity in a variety of settings.