Time to eat: the relationship between the number of people eating and meal duration in three lunch settings.

We conducted an observational study of customers in three different types of lunch settings: a worksite cafeteria, a fast-food restaurant, and a moderately priced restaurant, and assessed the relationship between meal duration and the number of people eating at each table (group size). Results suggest a significant positive correlation between group size and meal duration, collapsing over eating settings. Analysis of variance yielded significant main effects of both eating setting and of group size, indicating that meal durations were longest in the moderately priced restaurant and shortest in the fast-food restaurant. An interaction between group size and eating setting indicates that the magnitude of the group size effect on meal duration differed in the different situations, with the effect of group size on duration being smallest, but still significant, in the fast-food setting compared with the other two settings.