Comparison of two measures for assessing the volume of food waste in Swiss households

The huge amount of food wasted at the consumer or household level has severe environmental and economic consequences. In the present work, we compared two self-report measures for the assessment of food waste quantities at the household level in Switzerland. Participants (N = 223) were asked to complete an online food waste questionnaire (FWQ), in which they were instructed to report the average amount of food waste produced in their households. In the second step, participants were asked to maintain a food waste diary (FWD) for 21 days. They were instructed to write down all food waste items, including their relative amounts, as well as the reason and method for their disposal. Using correlation and regression analyses, we found that the amount of food waste reported on the FWQ and in the FWD were highly correlated, revealing similar patterns in terms of their psychological predictors. In the context of the range of different methods available for the assessment of household food waste, our study has provided valuable insights into two of the most used self-report measures. Similarities between and limitations of the methods have also been discussed. This knowledge can be used to contextualise the available results, to design future studies, and ultimately, to help develop intervention strategies to reduce household food waste.