In this study University of Alberta, Canada based researchers Osis, Worobets and Stefanyshyn set out "to examine ground kinetics early in stance while walking on a contaminated surface and assess the potential of kinetics to quantify risk of slipping." The authors indicate that previous research has focused primarily on what is referred to as the utilized coefficient of friction (UCoF) between the floor surface and the foot/shoe interface. This study, which focused on the very early stages of a slip, immediately following heel-strike, suggests shear force may be a better measure, and therefore predictor, of a slip/fall accident.