Individual and situational determinants of plastic waste sorting: an experience sampling method study protocol

Plastic waste management is one of the most challenging problems of our time. Until now, only 9% of the produced plastics has been recycled. In order to increase recycling, a behavior change towards sorting of plastic waste is needed. Therefore, the main aim of the study is to gain insight in the individual and situational determinants associated with plastic waste sorting behavior. The Integrated Framework for Encouraging Pro-environmental Behaviour will be used as the theoretical framework. This framework assumes that individual egoistic and hedonic values are negatively related to pro-environmental behaviour, whereas individual biospheric and altruistic values are positively related to pro-environmental behaviour. Situational cues can activate these values, resulting in (non) pro-environmental behaviour. Taking the Integrated Framework for Encouraging Pro-environmental Behaviour into account, this study will test the hypothesized associations between individual and situational determinants and plastic waste sorting behavior, using an ecological momentary assessment approach (Experience Sampling Method, ESM).

A signal-contingent scheme with semi-random intervals will be used for the ESM questionnaire. Over a period of seven consecutive days, an ESM-based smartphone app will prompt participants ten times a day to fill in a short questionnaire containing questions about situational determinants and plastic waste sorting behaviour. Participants will also complete an online questionnaire before and after the study measuring the individual determinants and plastic waste sorting behaviour.

ESM has many benefits over traditional surveys, such as improved ecological validity and the possibility to explore temporal relationships. The disadvantages of ESM are mainly related to the burden for the participants and the possibility of reactivity effects. The results will provide insight into the relationship between situational cues, individual values and plastic waste behaviour. The practical implications of the findings of this study can be of interest for policy makers in order to reach plastic waste reduction targets. Furthermore, the situational cues that activate values, which increase or decrease plastic waste sorting, can be targeted in interventions. The results of this study can also be relevant for further research studying and stimulating pro-environmental behaviour in general.