Development and evaluation of WillTry. An instrument for measuring children's willingness to try fruits and vegetables.

This paper describes the development and evaluation of the WillTry instrument, a psychometric tool designed to measure children's willingness to try fruits and vegetables. WillTry surveys were interviewer-administered to 284 children in an elementary school and summer day camps located in rural Mississippi and Arkansas (United States) communities. Factor analysis was used to determine construct dimensionality. Additional evaluation included internal consistency, test-retest reliability, and predictive validity. Factor analysis suggested a single dimension for the food items. The WillTry food scale had substantial reliability (intraclass correlation coefficients between 0.61 and 0.80) and sufficient internal consistency (Cronbach's alpha > or = 0.70). Results of the regression analysis for percent consumption of foods offered on WillTry response confirmed the predictive validity of the instrument. The results of these analyses provide psychometric evidence for the use of the WillTry instrument as a measure of willingness to try fruits and vegetables in rural, southern US children 5-14 years of age.