“…The categories with the highest percentages of positive outcomes were changing option-related efforts (88% of studies reported success, for instance Chan et al, 2013), providing social reference points (71%, for instance Hong, Ching, Fung & Seto, 1990), and using a combination of nudges (76%, for instance Hulgan et al, 2004). The categories with the highest percentages of mixed outcomes were facilitating commitment (40%, for instance Kullgren, Krupka, Schachter & Linden, 2018) and changing choice defaults (22%, for instance Ansher et al, 2014). Change option consequences had the highest percentage of null outcomes (50%, for instance Beidas et al, 2017), followed by translating information (44%, for instance Jousimaa et al, 2002).…”