Validation of a new hand-held electronic appetite rating system against the pen and paper method

This study describes the validation of a new electronic appetite rating system, and a statistical variance model for visual analogue scale (VAS) research. Thirty volunteers rated hunger, fullness, desire to eat, prospective intake, thirst and liking on 100 mm paper VAS and on 70 mm electronic VAS presented on a Dell™ Pocket PC, after consuming breakfast, in a repeated trial. The electronic method was comparable in relative accuracy and reproducibility to the paper method, with weak differences between tests (within-subject SD ≤ 14 mm). The data obtained were used to generate a model for VAS data variability.