The scaling of restraint and the prediction of eating

Abstract

The most frequently used measure of dietary restraint in controlled experiments involving arduous dieters is the Revised Restraint Scale (Herman & Mack, 1975). To date, researchers who have used the measure in controlled experiments have created a “high” versus “low” artificial dichotomy based on a median split of scores on the scale, apparently in an attempt to apply a standard analysis of variance model. The present study replicates a basic ice cream taste test experiment. It compares study results that emerge from using the Revised Restraint Scale as an artificial dichotomy (“factor”) versus a continuous independent variable in a general linear model. Results showed that an important joint effect emerged when restraint was treated as a continuous variable, which would likely have gone undetected using standard ANOVA, and that a greater proportion of variance could be accounted for in the continuous variable model. Researchers to date may have failed to optimally outline the nature of the relationship between dietary restraint and other variables that have been of interest.