A measurement model of youth physical activity using pedometer and self, parent, and peer reports
International Journal of Behavioral Medicine (2011) - Comment
pubmed: 20882445  doi: 10.1007/s12529-010-9118-5  issn: 1070-5503  issn: 1532-7558 

Nigel Chaumeton, Susan C. Duncan, Terry E. Duncan, Lisa A. Strycker