“…In open innovation, the majority of studies used aggregate measures of inbound practices investigating impacts of search depth and breadth (Laursen and Salter, 2006;Chiang and Hung, 2010), ease of knowledge access (Un et al, 2010), knowledge sourcing strategies (Fey and Birkinshaw, 2005;Kang and Kang, 2009;Kim and Park, 2010;Santamaria and Surroca, 2011) and degrees of openness (Innauen and Schencker-Wicki, 2011;Barge-Gil, 2013) on innovation performance. Only a few studies are available on the linkages between one specific inbound practice such as user involvement and innovation performance (Enkel et al, (2009) and Mazzola et al, (2012) for an overview).…”