Video evaluation for mastication validation in persons with Down's syndrome.

This article reports the second stage of a validation process. It investigates the discriminatory ability of three video indicators of mastication for a group of people with Down's syndrome, representing a target group with neurological disabilities. The variables were generated through video recordings of 11 adults with Down's syndrome and 12 healthy subjects eating four natural foods varying in hardness. The collected variables were masticatory time, number of masticatory cycles, and number of open masticatory cycles. The analytical approach attempts to test four hypotheses exploring the variations of the video indicators according to food hardness for both groups. It was demonstrated that masticatory time and the number of masticatory cycles have very strong, positive correlations and the number of open masticatory cycles has a fair, positive correlation with the food hardness rankings for both groups. Video evaluation of the test variables using real foods in people with Down's syndrome was found to be a valid means of evaluating aspects of their masticatory function.