Doctoral dissertations in logistics and supply chain management: a review of Nordic contributions from 2009 to 2014 <s> Extant literature on doctoral dissertations in logistics and supply chain management <s> A total of 317 logistics and logistics-related dissertations were published in Dissertation Abstracts between 1992 and 1998. Observations about these dissertation abstracts are offered and comparisons made with earlier research studies that examined dissertations published between 1970–1986 and 1987–1991. The number of dissertations published has plateaued although the number of colleges and universities granting doctoral degrees in the area have broadened, with several “new players” entering the arena. Some traditional topics within logistics are being researched to a lesser degree, while others such as supply chain management, general logistics, customer service/satisfaction, international logistics, and human resources/organizational issues, are being examined more frequently. <s> BIB001 </s> Doctoral dissertations in logistics and supply chain management: a review of Nordic contributions from 2009 to 2014 <s> Extant literature on doctoral dissertations in logistics and supply chain management <s> This paper presents an overview and summary of doctoral dissertations related to supply chain management (SCM) and logistics for the period of 1999-2004. A total of 410 entries from Dissertation Abstracts have been identified. Findings relating to this latest study period are presented and comparisons are made to previous compendiums covering 1970-1986, 1987-1991 and 1992-1998. A larger number of colleges and universities are granting degrees in SCM and logistics-related areas and some new institutions have entered the field, resulting in a distinct increasing trend in the absolute number of dissertations being published. The most popular dissertation topics in current research are decision support systems, inventory management, miscellaneous transportation (models, networks, policy issues, routing and scheduling) and supply chain management issues. Traditional transportation, warehousing and storage, distribution resource planning, just-in-time, Kanban and manufacturing resource planning topics have experienced downturns in terms of the number of doctoral dissertations being published. Relatively few dissertations in any of the time periods have been published on engineering logistics, human resources, location analysis, order processing and information systems, packaging and total quality management. <s> BIB002 </s> Doctoral dissertations in logistics and supply chain management: a review of Nordic contributions from 2009 to 2014 <s> Extant literature on doctoral dissertations in logistics and supply chain management <s> Purpose ::: ::: ::: ::: – The purpose of this paper is to identify Nordic doctoral dissertations in logistics and supply chain management (SCM) published from the years 2002 to 2008. The paper then seeks to analyze the identified dissertations by categorizing them in various dimensions, including but not limited to subject, methodology, and type of contribution. Subsequently, the paper compares the analysis of the dissertations with results obtained in a previous study that also concerned Nordic dissertations only published from 1990 to 2001, effectively opening up for longitudinal interpretations. ::: ::: ::: ::: ::: Design/methodology/approach ::: ::: ::: ::: – The paper is based on reviews of 70 Nordic doctoral dissertations within logistics and SCM published at relevant Nordic research institutions. All dissertations were reviewed according to a priori determined categories adopted from a similar, previous study in order to strengthen the validity of the longitudinal comparison. ::: ::: ::: ::: ::: Findings ::: ::: ::: ::: – This paper identifies a clear and significant trend towards: more dissertations based on a collection of articles than monographs; more dissertations focusing on manufacturing companies and fewer on carriers; a shift from a focal company perspective to more dyadic and supply chain‐related research and finally; and a decreasing focus on the philosophy in science. ::: ::: ::: ::: ::: Research limitations/implications ::: ::: ::: ::: – Despite the thorough method applied, there is possibility that a few dissertations might not have been identified in this paper. ::: ::: ::: ::: ::: Originality/value ::: ::: ::: ::: – This paper is a continuation of documenting the progress of doctoral work in logistics and SCM within the Nordic countries from the years 2002 to 2008. <s> BIB003 </s> Doctoral dissertations in logistics and supply chain management: a review of Nordic contributions from 2009 to 2014 <s> Extant literature on doctoral dissertations in logistics and supply chain management <s> The purpose of this article is to examine the output of logistics and supply chain-related dissertation research during the period, 2005–2009, and compare that output with earlier published dissertations from 1970 to 2004. Doctoral students and faculty members can identify emerging areas of research based on the year-by-year trends in topical coverage. Qualitative research analysis of 609 doctoral dissertations published by Dissertation Abstracts International over a 5-year period (2005–2009) was performed. Results suggest that future prospects for additional dissertations being published in logistics and supply chain-related areas are excellent. Many dissertations are emanated from colleges of engineering and business. The prominent research methodologies employed by doctoral students are modeling, simulation, and empirical quantitative methods. More colleges/universities are graduating doctoral students in these areas. Some shift is occurring with respect to the specific colleges/universities that are leading the way in terms of generating the largest number of logistics and supply chain graduates. <s> BIB004
Several authors have analyzed and classified doctoral dissertations in logistics and SCM, both within the Nordic countries as well as the USA. In this section, nine prior studies-seven American studies and two Nordic studiesare briefly mentioned so as to identify the trends in topical coverage through the years and to see whether there are any similarities between the topics chosen by PhD students across the Atlantic. The first study of compendiums of PhD research in logistics conducted by Stock back in 1987 [28] examined 684 dissertations from the period 1970-1986  . Subsequent reviews were conducted in (1) 1993 covering 422 American dissertations that were completed in the period of 1987-1991  and (2) 2001 with an analysis of 317 PhD dissertations completed in the period of 1992-1998 BIB001 . In 2006, Stock completed his fourth review of PhD dissertations together with Broadus BIB002 . This study showed a distinct increasing trend in the number of dissertations within SCM-and/or logistic-related areas in the period from 1999 to 2004 when compared to the period covered by the 2001 study. But surprisingly, the count between 1999 and 2004 fell short of the overall levels of 1987-1991. A more interesting finding of the 2006 study was that the dissertations were more multifaceted due to the fact that they closely mirrored the cross-functional and boundary spanning nature of logistics; at the same time, their multifaceted nature made the classification task more difficult. Another American study was conducted by Das and Handfield [8] wherein the authors investigated 117 PhD dissertations from the period 1987-1995 in order to evaluate the intellectual health of the purchasing discipline. The study was an extension of a previous research on purchasing dissertations conducted by Williams  to identify the key focus areas of research in the prior decade. In this study, Williams concluded that the key focus areas covered were supplier selection and development, information systems, organizational and measurement issues, negotiation and purchasing ethics. The most recent review covering US dissertations was conducted by Nakhata et al. BIB004 . In this study, the authors reviewed 609 doctoral dissertations completed between 2005 and 2009. The number of identified dissertations in this study is significantly larger than the four reviews conducted by Stock and colleagues and clearly reflects a significant increase in colleges/universities graduating doctoral students within logistics-and supply chain-related areas. Nakhata et al. BIB004 also point out that a forthcoming retirement of academic ''baby boomers'' during the period 2005-2020 may explain the increase in the PhD production. The most prominent research methodologies employed by doctoral students in the study of Nakhata et al. BIB004 are modeling, simulation and empirical quantitative methods. Two earlier studies of Nordic doctoral dissertations within logistics and SCM have been disseminated in academic journals. The first was developed by Gubi et al. [13] , who reviewed 71 Nordic dissertations published between 1990 and 2001. Most of the dissertations were published as monographs with manufactures and carriers as the primary entity of analysis. The most recent Nordic contribution is by Zachariassen and Arlbjørn BIB003 wherein the authors analyze the development in Nordic doctoral research in logistics and SCM from the years 2002-2008. As opposed to Gubi et al. [13] , Zachariassen and Arlbjørn BIB003 found more dissertations based on a collection of articles, which was reflective of a response to increase publication pressure. In contrast to the Gubi et al.'s [13] study, the primarily entity of analysis of most dissertations was the manufacturing companies. While prior reviews showed a focal company perspective, the review of Zachariassen and Arlbjørn BIB003 documented a shift toward an inter-organizational perspective covering dyadic and supply chain units of analysis. Additionally, according to Zachariassen and Arlbjørn BIB003 , there has also been a decreased focus on the philosophy of science, since most dissertations were being published as collections of articles.