Figure 1:

A number of variables to explain the portion size effect (PSE) have been identified and are shown here. These include environmental and food-related factors as well as consumer characteristics. In addition, pre-meal decision making can impact portion selection, which would influence subsequent intake. Boxes with single solid lines represent overarching influences (explanatory variables), while the circles are the moderators related to these variables. Dashed lines appear around a variable that may underlie a moderator’s role in the PSE, but is not proven. Arrows with solid lines indicate strong evidence of an influence on the PSE, while dashed lines represent some evidence of an influence. Bi-directional arrows are used to highlight moderators that likely fall under a related explanatory variable, such as value or orosensory processing.