Synthesis Approach for Analyzing Waste Minimization in Aotearoa New Zealand
Many of society’s most pressing problems, such as climate change, poverty, and waste, are categorized as “wicked” problems because they are seemingly resistant to change. Interventions designed to address these problems can produce unintended consequences, which then perpetuate the problem. Evaluating the effectiveness of such interventions is challenging and requires understanding of the social systems in which the problems are embedded. Multimethodology approaches can support such holistic understanding by combining different methodologies which complement and overlap with each other. This article reports on a study that combined two different methodologies—realist review and qualitative system dynamics. The result was a program theory for waste minimization interventions in Aotearoa New Zealand and a causal loop diagram, which allowed us to identify potential leverage points for change. The two methodologies highlighted different aspects of the problem in complementary ways. For example, the first program theory proposition emphasized the important role of people who were critically conscious of the need for sustainability, while the causal loop diagram showed that there needed to be enough critically conscious people for change to be embedded in the system. The program theory’s third and fourth propositions noted the important role of leadership and resource allocation in shifting interventions away from waste management initiatives, such as recycling plastic bags, towards waste minimization initiatives, such as banning single-use plastic bags. The causal loop diagram demonstrated why resource allocation to waste management initiatives, such as recycling, are not effective in addressing the overall problem of waste by showing the feedback loops that operate in the system. Such insights show that realist reviews and qualitative system dynamics can usefully complement each other for greater understanding of wicked problems.