تاثیر یکپارچه سازی زنجیره تامین بر پاسخگویی: اثر تعدیل با استفاده از یک شبکه تامین کننده بین المللی

This study reveals that in supply networks both external and internal integration practices have a significant and positive impact on responsiveness. The use of an international supplier network acts as a contingency factor on the relationship between external integration practices and responsiveness, as in an international context the effect on performance is amplified. Conversely, the impact of internal integration on responsiveness is not moderated by the use of international suppliers. These evidences suggest managers how to properly tune the level of adoption of integration practices according to the degree of supplier network internationalization.

The concept of supply chain integration (SCI) is a pivotal issue in supply chain management (SCM) literature. Though most scholars recognize that SCI can contribute to improving supply network performance (Frohlich and Westbrook, 2001 and van der Vaart and van Donk, 2008), the debate is still open in the literature about how to maximize this impact. For instance, Swink et al. (2007) note that the simultaneous integration of customers and suppliers is considered a necessary condition to assure the achievement of significant benefits. However, Mouritsen et al. (2003) point out that similar levels of implementation of SCI practices do not bring about equal improvements whatever the context, hence, it is essential to investigate the conditions under which SCI can be more beneficial. In the same vein, van Donk and van der Vaart (2005) demonstrate that in certain conditions a low level of integrative practices could be the best strategy to pursue. From the above it seems to emerge that some factors which are exogenous to the relationship between SCI and performance may act as moderators of this causal link. It is interesting to note that, as stated by Vickery and Dröge (2011), only a few research studies have been conducted on interactions between integration mechanisms and other external factors, such as environmental turbulence. Also Wong et al. (2011) lament that academic knowledge on the moderating effect of environmental uncertainties on the SCI–performance relationships still remains inadequate, due to the mixed findings obtained by the recent studies. Among the exogenous factors affecting the SCI–performance relationship, supplier network internationalization plays a key role as it is recognized as a disruptive source of uncertainty that forces companies to cooperate with customers and suppliers to efficaciously managing procurement, production and delivery plans in order to sustain cost, quality and delivery performances (Handfield and Nichols, 1999, Vachon and Klassen, 2002 and Camuffo et al., 2007). Nevertheless, despite being a timely issue, we did not find quantitative studies investigating the interactions between SCI practices and the degree of supplier network internationalization. Instead, as Bozarth et al. (2009) point out, there is the need to assess how internationalization of the supplier network influences the impact of SCI practices on performances, especially on time-related ones. In fact, the authors argue that though most of the research on the impact of SCI on performance has concentrated on cost-issues, the focus of supply network performances is moving from criteria which are exclusively based on cost to criteria related to responsiveness, such as delivery reliability, speed and flexibility. In an international supply network context, problems due to responsiveness (e.g. delays in deliveries, long lead times) can quickly generate further problems that cascade forward through the chain. Hence, it can be argued that it is in the international context that SCI practices such as enhanced communications with customers and suppliers can better support supply network responsiveness. This paper aims to investigate whether supplier network internationalization positively moderates the relationship between the adoption of SCI practices and responsiveness performance. This means that when companies rely on international suppliers the benefit on responsiveness of implementing SCI is expected to be greater. The present study contributes to the advancement of theory by providing better understanding on the implementation of SCI practices in an international supply context, on the relationship between SCI and responsiveness performance and, in particular, on the conditions in which the implementation of SCI practices guarantees higher performance improvements. From a managerial perspective, this paper underlines the importance for organizations to understand that SCI integration can be a powerful approach to improving responsiveness, and that it is essential especially in case of international supplier networks. This represents the key contribution of the paper to the literature because, as pointed out by O’Leary-Kelly and Flores, 2002 and Wong et al., 2011, the costs required to implement SCI create an urgent need to understand the conditions to maximize performance improvements. Therefore, this paper can be positioned in the research stream that refers to the seminal papers by Cooper et al., 1997, Fisher, 1997, Stock et al., 2000 and Choi and Hong, 2002, who suggest the adoption of a contingency approach to studying SCI practices, because the relationship between supply chain practices and performance is contingent upon how supply networks have been designed.

This research adopts a contingency approach to studying SCI, by investigating not only whether external and internal integration practices significantly and positively improve firm’s responsiveness, but also whether this impact can be magnified in international supplier networks. The contributions of this paper to the literature are several: • both EI and II have a significant and positive impact on firms’ performance in terms of responsiveness; • the use of an international supplier network is a contingency factor influencing the relationship between EI and responsiveness performance and it positively moderates the impact of EI on responsiveness; • the use of an international supplier network is not a contingency factor influencing the relationship between II and responsiveness performance as it does not significantly moderate the impact of II on responsiveness. The first contribution can be positioned in the theoretical debate reported in Section 2.2. Scholars who analyzed the impact of SCI practices on performance using the lens of the resource-based view, transaction cost economics and organizational information processing theory generally agree that a higher level of SCI can improve firm performance. However, quantitative studies are not unanimous (Fabbe-Costes and Jahre, 2008 and van der Vaart and van Donk, 2008). Our results contribute to the debate supporting the stream of research which advocates the adoption of SCI as an important driver in improving responsiveness performance (Flynn et al., 2010, Danese, 2011 and Yi et al., 2011). The second contribution concerns the growing contingency research stream in SCM (Danese et al., 2006, Sousa and Voss, 2008 and Flynn et al., 2010). Although several authors have advocated that in order to advance theory on the SCI–performance relationship potential contingency effects should be no longer ignored, empirical studies on the contexts where integration is more beneficial are still scarce. This research advances a significant contribution to fill this research gap, by proving that in international supplier networks EI is particularly useful in order to improve firm responsiveness. Evidence based on a large sample that ISN can positively moderate the EI–responsiveness relationship is novel in the literature, and thus represents an original contribution of this research. Several authors recognize that international supplier networks generate greater complexity in managing material and information flows compared to local networks (Overby and Min, 2001, Seeley et al., 2001, Trent and Monczka, 2003 and Fliess and Busquets, 2006). This research contributes to these studies by demonstrating that in an international sourcing context, external integration can help to deal with supply uncertainty and increased complexity in material management, thus offsetting responsiveness performance limitations. The third result further contributes to literature on supply network internationalization and in particular to the debate on the implementation of SCI practices in international contexts (see Section 2.4). As explained above, international supplier networks are characterized by more complex and vulnerable materials and information flows compared to domestic ones. Some authors argue that it is for companies relying on international supplier networks that II and EI have the largest effect on responsiveness because these practices support managers in facing the complexity of logistics flows and reducing their vulnerability (Overby and Min, 2001, Flynn et al., 2010 and Yi et al., 2011). This study partially confirms this view. While the use of an international supplier network positively moderates the impact of EI on responsiveness, it does not significantly influence the impact of II on the same performance. Therefore, in the case of international supplier networks the effect of SCI practices on responsiveness can be amplified by leveraging on fast and reliable communication flows across supply network partners rather than within the company. In conclusion, there are some limitations of this study that suggest some proposals for future research. First, as in other surveys on SCM-related issues (Frohlich and Westbrook, 2001, Kim, 2009 and Danese and Romano, 2011), in this study we collected information on the level of integration of the focal firm with its suppliers and customers. This limits the focus of this research to the immediate network of the focal company. Instead, SCI could go beyond the immediate network, by involving second/third tier customers/suppliers. We think that collecting data from supply chains (i.e. at least two, or three or more stages of the supply chains) could be very appropriate in order to evaluate the integration of the total supply network. A further possible limitation of this research could derive from its setting (i.e. machinery, electronic and transportation components sectors), which could limit the generalizability of our findings. Therefore, future research should replicate and integrate our model by considering samples from other industries. In addition, future studies could focus on SCI practices related to quality and innovation management. In fact, while in this research we studied SCI practices supporting the order fulfillment process and their impact on responsiveness, a different focus in the identification of SCI practices could be appropriate to investigate their impact on other key performances, such as quality and product innovation, and the potential moderating role of supply network internationalization. Finally, future research could address the impact of geographical location of suppliers on the relationship between SCI practices and performance. In this study we didn’t find significant country difference, mainly because our dataset provides information on the location of the production plants, but not of their suppliers. Indeed, two plants located in the same country could rely on very different supplier networks. For instance it would be very interesting to study whether for a plant located in a European country it could be more critical to rely on suppliers located in the Far-East rather than in North-Africa in terms of impact on responsiveness.