Creating a Physical Activity Self-Report Form for Youth Using Rasch Methodology.

Measurement of youth's physical activity levels is recommended to ensure that children are meeting recommended activity guidelines. This article describes the creation of an instrument to measure youth's levels of physical activity, where a strong test validation perspective (Benson, 1998) was followed to create the scale. The development process involved a mixed-method (qualitative followed by quantitative) framework. First, focus groups were conducted, where results informed item creation. Next, three alternative forms were created with different response formats to measure childrens' frequency of participation in various physical activities and intensity of participation. Lastly, a sample of over 500 middle school children was obtained, where three different response scales were investigated. The optimal scale considered measurement of physical activity using a three-point Likert frequency; intensity of activity participation did not strongly contribute to the measurement of children's activity levels. The final version form is thought to be acceptable for use with children in surveillance and large-group studies, as well as in smaller sample applications.