Unraveling the dimensions of supplier involvement and their effects on NPD performance: a meta-analysis

We study the relationship between supplier involvement in New Product Development and performance. The current literature is scattered and fragmented with studies reporting mixed empirical evidence for a variety of concepts related to ‘Early Supplier Involvement’. We conduct a systematic review and meta‐analysis of the existing literature to reconcile conflicted findings, revise and refine theoretical perspectives, and provide evidence‐based scholarly and practical implications. To achieve these aims, we unravel the general relationship by considering three factors. First, we delineate different types of performance outcomes, mainly related to NPD efficiency (e.g., speed) and NPD effectiveness (e.g., product quality). Second, we distinguish between the moment and the extent of supplier involvement, related to different theoretical perspectives on external knowledge integration. Third, we disentangle multiple levels of analysis that are seemingly obscured in the literature, specifically the project and organizational levels. We find that extensive supplier involvement has positive effects on NPD efficiency and effectiveness, whereas earlier supplier involvement only to some degree affects NPD efficiency and not effectiveness. In conclusion, our meta‐analysis based on 11,420 observations from 51 studies provides strong theoretical and practical insights on the important phenomenon of supplier involvement.