BPMJ-03-2014-0019

BPMJ-03-2014-0019

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  Business Process ManagementJournal A systematic review of Lean Six Sigma for the manufacturing industry Saja Ahmed Albliwi Jiju Antony Sarina Abdul halim Lim Article information: To cite this document: Saja Ahmed Albliwi Jiju Antony Sarina Abdul halim Lim , (2015),"A systematic review of Lean Six Sigma for the manufacturing industry", Business Process Management Journal, Vol. 21 Iss 3 pp. 665 - 691 Permanent link to this document: http://dx.doi.org/10.1108/BPMJ-03-2014-0019 Downloaded on: 31 May 2015, At: 15:44 (PT) References: this document contains references to 63 other documents. To copy this document: permissions@emeraldinsight.com The fulltext of this document has been downloaded 94 times since 2015* Users who downloaded this article also downloaded: Saja Albliwi, Jiju Antony, Sarina Abdul Halim Lim, Ton van der Wiele, (2014),"Critical failure factors of Lean Six Sigma: a systematic literature review", International Journal of Quality & Reliability Management, Vol. 31 Iss 9 pp. 1012-1030 http://dx.doi.org/10.1108/IJQRM-09-2013-0147 Diego Pacheco, Isaac Pergher, Guilherme Luís Roehe Vaccaro, Carlos Fernando Jung, Carla ten Caten, (2015),"18 comparative aspects between Lean and Six Sigma: Complementarity and implications", International Journal of Lean Six Sigma, Vol. 6 Iss 2 pp. 161-175 http:// dx.doi.org/10.1108/IJLSS-05-2014-0012 M.P.J. Pepper, T.A. Spedding, (2010),"The evolution of lean Six Sigma", International Journal of Quality & Reliability Management, Vol. 27 Iss 2 pp. 138-155 http:// dx.doi.org/10.1108/02656711011014276 Access to this document was granted through an Emerald subscription provided by 173423 [] For Authors If you would like to write for this, or any other Emerald publication, then please use our Emerald for Authors service information about how to choose which publication to write for and submission guidelines are available for all. Please visit www.emeraldinsight.com/authors for more information. About Emerald www.emeraldinsight.com Emerald is a global publisher linking research and practice to the benefit of society. The company manages a portfolio of more than 290 journals and over 2,350 books and book series volumes, as well as providing an extensive range of online products and additional customer resources and services. Emerald is both COUNTER 4 and TRANSFER compliant. The organization is a partner of the Committee on Publication Ethics (COPE) and also works with Portico and the LOCKSS initiative for digital archive preservation. DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  *Related content anddownload information correct at time of download. DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  A systematic review ofLean Six Sigma for the manufacturing industry Saja Ahmed Albliwi, Jiju Antony and Sarina Abdul Halim Lim Department of Business Management, Heriot-Watt University, Edinburgh, UK Abstract Purpose – The purpose of this paper is to explore the most common themes within Lean Six Sigma (LSS) in the manufacturing sector, and to identify any gaps in those themes that may be preventing users from getting the most benefit from their LSS strategy. This paper also identifies the gaps in current literature and develops an agenda for future research into LSS themes. Design/methodology/approach – The following research is based on a review of 37 papers that were published on LSS in the top journals in the field and other specialist journals, from 2000 to 2013. Findings – Many issues have emerged in this paper and important themes have cited which are: benefits, motivation factors, limitations and impeding factors. The analysis of 19 case studies in the manufacturing sector has resulted in significant benefits cited in this paper. However, many gaps and limitations need to be explored in future research as there have been little written on LSS as a holistic strategy for business improvement. Practical implications – It is important for practitioners to be aware of LSS benefits, limitations and impeding factors before starting the LSS implementation process. Hence, this paper could provide valuable insights to practitioners. Originality/value – This paper is based on a comprehensive literature review which gives an opportunity to LSS researchers to understand some common themes within LSS in depth. In addition, highlighting many gaps in the current literature and developing an agenda for future research, will save time and effort for readers looking to research topics within LSS. Keywords Benefits, Lean Six Sigma, Future research, Impeding factors, Limitations, Motivation factors Paper type Literature review 1. Introduction In recent years, Lean and Six Sigma (LSS) have become the most popular business strategies for deploying continuous improvement (CI) in manufacturing and service sectors, as well as in the public sector. CI is the main aim for any organization in the world to help them to achieve quality and operational excellence and to enhance performance (Thomas et al., 2009; Assarlind et al., 2012). Womack et al. (1990) defined Lean as a “dynamic process of change, driven by a set of principles and best practices aimed at continuous improvement.” The root of Lean lies on Toyota Production System (TPS) which established shortly after the Second World War in 1940s in Japan by Taiichi Ohno (Womack et al., 1990; Womack and Jones, 2003; Maleyeff et al., 2012). As a result of the publication of the book The Machine that Changed the World by Womack in 1990, TPS has adopted by the Americans and known in the western countries as Lean manufacturing (Akbulut-Bailey et al., 2012). Business Process Management Journal Vol. 21 No. 3, 2015 pp. 665-691 © Emerald Group Publishing Limited 1463-7154 DOI 10.1108/BPMJ-03-2014-0019 Received 5 March 2014 Revised 10 September 2014 31 October 2014 Accepted 3 December 2014 The current issue and full text archive of this journal is available on Emerald Insight at: www.emeraldinsight.com/1463-7154.htm This study was sponsored by a grant from King Abdulaziz University, Jeddah, Saudi Arabia. The first author is a recipient of PhD studentship award from King Abdulaziz University. The funding body has no role in the study design, data collection and analysis, decision to publish or preparation of the manuscript. 665 A systematic review of Lean Six Sigma DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  Lean focussed onelimination of non-value added activities and waste (or “muda”) in industry (Womack and Jones, 2003; Naslund, 2008). The seven wastes are: motion, overproduction, over processing, lead time, rework, inventory and defects (Chakravorty and Shah, 2012; Lee and Wei, 2009; Bhuiyan et al., 2006; Vinodh et al., 2011). In addition, two more types of waste have appeared in literature recently as stated by Vinodh et al. (2012): underutilization of people’s creativity and environmental waste. Lean also focusses on reduction of total cycle time (Drohomeretski et al., 2013; Lee and Wei, 2009) and reduction of lead time (Hu et al., 2008; Chen et al., 2010). Lean consists of many tools and techniques for improvement such as the Kanban system, 5S, Cause and Effect analysis (C&E), Value Stream Mapping (VSM) and many others (Drohomeretski et al., 2013; Chen and Lyu, 2009; Thomas et al., 2009). However, Lean still contains some challenges that face organizations such as the fundamental shift required in an organization’s culture. Womack and Jones (2005) argued that the culture change is a big challenge in Lean as the implementation of Lean requires a fundamental shift in the way of stakeholders’ thinking and in the nature of the relationship between them to reduce cost and waste. Six Sigma is defined as “a well-established approach that seeks to identify and eliminate defects, mistakes or failures in business processes or systems by focusing on those process performance characteristics that are of critical importance to customers” (Antony, 2008). Six Sigma is a statistical methodology that aims to reduce variation in any process (Chakravorty and Shah, 2012; Naslund, 2008), reduce costs in manufacturing and services, make savings to the bottom line, increase customer satisfaction (Drohomeretski et al., 2013; Shah et al., 2008; Manville et al., 2012; Naslund, 2008), measure defects, improve product quality, and reduce defects to 3.4 parts per million opportunities in an organization (Lee and Wei, 2009; Chen and Lyu, 2009). These are done through powerful analytical and statistical tools and techniques such as Quality Function Deployment (QFD), Failure Mode and Effect Analysis (FMEA), Statistical Process Control (SPC), Design of Experiments (DOE), Analysis of Variance (ANOVA), Kano Model, etc. (Bhuiyan et al., 2006). Some of these tools have adopted from TQM as Six Sigma in itself has derived from the TQM movement (Klefsjö et al., 2001; Andersson et al., 2006; Aboelmaged, 2010; Chiarini, 2013a, b). Though, the high cost of Six Sigma training is a barrier for many organizations to deploy this methodology. Other disadvantages are the time it appears to take to both implement Six Sigma and for the results to become visible (Pepper and Spedding, 2010; Timans et al., 2012). In fact, deploying Six Sigma in isolation cannot remove all types of waste from the process, and deploying Lean management in isolation cannot control the process statistically and remove variation from the process (Corbett, 2011). Therefore, some companies have decided to merge both methodologies to overcome the weaknesses of these two CI methodologies when they have been implemented in isolation and to come up with more powerful strategy for CI and optimizing processes (Bhuiyan et al., 2006). In fact, LSS are completing each other and there is an obvious relation between both methodologies, which makes it possible for the synergy of the two methodologies (see Figure 1) (Hu et al., 2008). Therefore, the integration of these two approaches gives the organization more efficiency and affectivity and helps to achieve superior performance faster than the implementation of each approach in isolation (Salah et al., 2010). The popularity and the first integration of LSS were in the USA in the George Group in 1986 (Chakravorty and Shah, 2012; Vinodh et al., 2012). However, the term LSS was first introduced into literature around 2000 LSS teaching was established in 2003 as 666 BPMJ 21,3 DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  part of theevolution of Six Sigma (Timans et al., 2012). Since that time, there has been a noticeable increase in LSS popularity and deployment in the industrial world (Shah et al., 2008), especially in large organizations in the west such as Motorola, Honeywell, General Electric and many others (Timans et al., 2012; Laureani and Antony, 2012) and in some small- and medium-sized manufacturing enterprises (SMEs) (Kumar et al., 2006). LSS was defined by Snee (2010) as “a business strategy and methodology that increases process performance resulting in enhanced customer satisfaction and improved bottom line results.” LSS methodology aims to improve capability in an organization, reduce production costs (Lee and Wei, 2009; Chen and Lyu, 2009) and maximize the value for shareholders by improving quality (Laureani and Antony, 2012). A review of case studies has identified many reasons for organizations to implement an LSS strategy in the new millennium: for example, to improve their business performance and operational efficiency, especially in the growth of global markets, to improve product quality (Vinodh et al., 2012), reduce production costs and enhance customer satisfaction (Chen and Lyu, 2009). More recently, LSS comprises the implementation of DMAIC methodology with a mix of appropriate tools from the Lean toolkit and Six Sigma at each step of DMAIC (Kumar et al., 2006; Vinodh et al., 2011). Moreover, the role of DMAIC in LSS is as a framework and a solid base for successful implementation (Chakravorty and Shah, 2012). Pickrell et al. (2005) argued that LSS uses the Six Sigma framework as a platform for initiatives in conjunction with Lean principles and tools. As a result of ideas about the integration of LSS and the interest in LSS by organizations, researchers have the interest to publish more papers on LSS to try to come up with a comprehensive approach to achieve CI. For instance, a number of academics have developed an integrated strategy such as the strategies that were developed by Thomas et al. (2008), Snee and Hoerl (2007), Pepper and Spedding (2010) and so on. Other researchers have developed a framework for the successful integration of LSS, such as Salah et al. (2010), Alsmadi and Khan (2010) and Kumar et al. (2006). The benefits and the critical success factors of applying LSS in parallel are also Six Sigma 1980s TPS 1940s Lean Lean Six Sigma 2000 Powerful strategy for optimizing process with no waste in process or defects in products, low costs, and increasing bottom line, customer satisfaction and employee morale 1990 -Eliminate defects -Reduce variations in processes -Reduce quality cost -Demonstrate hard cash savings to the bottom-line -Increase customer satisfaction -Improve Quality -Use statiscal tools -Remove waste -Improve efficiency -Improve flow -Determine value added and non-value added activities -Use non-statistical tools Source: Adopted Shahin and Alinavaz (2008) Figure 1. Lean and Six Sigma integration 667 A systematic review of Lean Six Sigma DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  noted in manycase study papers in both the manufacturing and the service sector (Akbulut-Bailey et al., 2012; Pickrell et al., 2005; Hardeman and Goethals, 2011). However, not all organizations have gained real benefits from LSS as unsuccessful implementation rendered it ineffective. In addition, there are many gaps that need to be addressed in LSS literature such as benefits, motivation factors, challenges and limitations (Pepper and Spedding, 2010; Laureani and Antony, 2011). Hence, the purpose of this paper is to address such gaps within LSS that are most important within the manufacturing sector and allow them to achieve the most benefits from this strategy, as well as to identify the gaps and give recommendations for future research. There are also noticeable limitations in the fields of research into areas of LSS in the manufacturing sector as highlighted in this paper. 2. Methodology To achieve the overall aims of this research, the authors are systematically reviewing the literature. According to Okoli and Schabram (2010), a systematic literature review is “a systematic, explicit, comprehensive and reproducible method for identifying, evaluating and synthesizing the existing body of completed and recorded work produced by researchers, scholars and practitioners.” Tranfield et al. (2003) stated that systematic review has become a “fundamental scientific activity.” One of the advantages of undertaking the systematic review approach is becoming aware of the breadth of research and the theoretical background in a specific field. Researchers believe that it is very important to conduct a systematic review in any field, to understand the level of previous research that has been undertaken and to know about the weaknesses and areas that need more research in the field (Okoli and Schabram, 2010). Interestingly enough, only two systematic reviews have been published in LSS, which were carried out by Glasgow et al. (2010) in healthcare and the second review has been done by Prasanna and Vinodh (2013) for SMEs. In addition, a general structured review for LSS has been done by Zhang et al. (2012) and a few number of traditional literature reviews on LSS has appeared recently, e.g. Wang et al. (2012) and Ahmed et al. (2013). Authors have argued that there is a clear need for more systematic reviews to be carried out in the field of LSS to bridge the gap in previous literature. Therefore, this paper aims to present a systematic literature review of all the papers that existed in top journals and specialist journals in LSS from 2000 to 2013, to explore the most common themes that have been published in the field of LSS and to explore the gaps in each theme in the manufacturing industry. Top journals are determined by using the journal ranking list in the International Guide to Academic Journal Quality (ABS, 2011; Harzing 2012). 2.1 Approach and phases In this paper, the approach includes ten fundamental processes for conducting a systematic literature review which are: (1) Research purpose and objective: the purpose and objectives are clearly identified after a review of most common gaps that appeared in the literature. (2) Develop research protocol: the protocol includes the study scope, strategy, criteria, quality assessment, and data extraction and so on. This protocol will be followed during the systematic literature review process. 668 BPMJ 21,3 DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  (3) Establish relevancecriteria: the research criteria help to ensure that we include only the papers most relevant to the research question, and exclude unrelated papers. (4) Search and retrieve the literature: electronic research for relevant articles in top academic and specialist journals, and hand research in bibliography lists if needed. (5) Selection of studies: dependent on research criteria. (6) Quality assessment for relevant studies: using appropriate tools to assess articles for quality. Each article should be scored for its quality depending on the methodology used. (7) Data extraction: extract the relevant data from each study included in the review. (8) Synthesis of studies (analysis): using appropriate techniques, such as quantitative or qualitative analysis, or both for combining the extracted facts. (9) Reporting: reporting the systematic literature review in detail as well as the results of the review. (10) Dissemination: publishing the systematic review in an academic journal to make a contribution to knowledge in the field. These processes are underlain by three phases as shown in Figure 2. The process and phases in this approach have been adapted from several academic sources such as Okoli and Schabram (2010), Tranfield et al. (2003) and Thomas et al. (2004). 2.2 Criteria Inclusion and exclusion criteria are stated in order to make it clear to the reader why some articles with which they are familiar have been excluded from the review (Booth et al., 2012). Planning the Review Conducting the Review Documenting the Review Report the Research Dissemination Apply the CriteriaResearch Purpose Research Protocol Search the Literature selection of studies Quality Assessment Data Extraction and Synthesis Sources: Okoli and Schabram (2010), Tranfield et al. (2003) and Thomas et al. (2004) Figure 2. Summary of research phases and processes 669 A systematic review of Lean Six Sigma DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  Okoli and Schabram(2010) argue that simplifying research by criteria by first reviewing the title, and then the abstract when needed, helps the researcher to save time and effort. Adopting this approach, the authors have gone through papers by title and then abstract where required, and by this means have included all papers that meet the inclusion criteria, but use of this method means that not all unrelated papers could be excluded (see Table I). 2.3 Material and outcomes The “journal” search for research literature was done through 42 top academic journals and nine specialist journals in the field of Six Sigma, Lean and LSS that are published in nine well-known databases: Emerald, American Society for Quality (ASQ), Inderscience, Taylor & Francis, Elsevier, Informs, IEEE Xplore, John Wiley & Sons and ProQuest. Search strings have been used such as: ((lean) and (six sigma) or (lean six sigma) or (lean sigma) or (continuous improvement) and (manufacturing) and (case study) not service). Meanwhile, the literature search was limited to the English language only. However, some journals were excluded from the review due to the absence of related articles to the research criteria. This search of journals and databases illustrated that there were no research articles related to LSS to be found before 2003. This result has supported by many researchers such as Wang et al. (2012) who have reported that there was no LSS publication to be found before the year 2003. The most common themes that emerged in the literature are benefits, motivation factors, limitations, impeding factors. These themes have been presented in this paper as they are the most common themes in literature (Tables II and III). Inclusion Exclusion Articles published between 2000 and 2012 Any publication before 2000 Articles published in two stars journals in minimum In operation management topics Articles published in specialists journals Low-ranking journals (one star or less) Non-relevant journals Papers highlighting benefits and motivation factors for LSS deployment in the manufacturing sector Papers related to other sectors or other themes such as CSF, challenges, etc. Academic journals Books, online sites and gray literature (conferences, reports, technical reports, etc.) Table I. Research criteria Journal name and database Start date Entries papers Relevant papers Country of origins International Journal of Lean Six Sigma 2010 24 7 UK International Journal of Six Sigma & Competitive Advantages 2004 24 5 UK International Journal of Productivity & Performance Management 2004 6 2 UK Quality Management Journal (ASQ) 1993 0 0 USA Six Sigma Forum Magazine (ASQ) 2001 9 9 USA Quality Progress (ASQ) 1995 1 1 USA Quality Engineering (ASQ) 2004 7 0 USA Journal for Quality & Participation (ASQ) 1987 0 0 USA Journal of Quality & Technology (ASQ) 1969 0 0 USA Table II. LSS specialist journals and the number of hits (papers) in each journal 670 BPMJ 21,3 DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  3. Results anddiscussion After a long journey and a deep review of the available literature on LSS, a number of key issues have been identified, and these are described in this section of the paper. 3.1 Growth of LSS publications in the manufacturing sector There is a noticeable increase in the number of LSS publications in academic journals since 2003 (see Figure 3), which is the year of the first published paper on LSS in the manufacturing sector, by William and Willie, which presented the Honeywell experience Journal name Entries papers Relevant papers International Journal of Production Research 2 0 International Journal of Production Economics 0 0 European Journal of Operational Research 0 0 Journal of the Operational Research Society 1 1 Production Planning and Control Journal 4 4 International Journal of Operations and Production Management 1 0 Manufacturing and Service Operations Management Journal 7 0 International Journal of Management Science (OMEGA) 6 0 Sloan Management Review (MIT) 7 0 Management Science 1 0 Harvard Business Review 12 0 Production and Operations Management 1 0 Journal of Operations Management 1 0 Technovation 1 0 Decision Sciences Journal 0 0 International Journal of Quality and Reliability Management 8 1 TQM Journal 7 2 Journal of Manufacturing Technology Management 3 1 Quality and Reliability Engineering International 3 1 International Journal of Technology Management 1 1 Manufacturing Engineer (IEE Transactions) 3 1 TQM and Business Excellence 2 0 European Journal of Industrial Engineering 1 1 Operations Research 0 0 Mathematics of Operations Research 0 0 Decision Analysis 0 0 Manufacturing & Service Operations Management 0 0 Interfaces 1 0 Naval Research Logistics (star journal) 0 0 Operations Research Letters 0 0 IIE Transactions 4 0 Annals of Operations Research 2 0 Mathematical Programming 0 0 Transportation Science 0 0 Journal of the American Statistical Association 2 0 Computers & Operations Research 1 0 Decision Support Systems 1 0 Academy of Management Journal 1 0 Business Process Management 1 0 British Journal of Management 0 0 California Management Review 0 0 European Business Review 0 0 Table III. Number of Lean, Six Sigma and LSS hits (papers) in academic journals 671 A systematic review of Lean Six Sigma DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  in implementing LSS.While the first known integration of LSS in that sector was in 1986 in the George Group in the USA (Salah et al., 2010). As shown in Figure 3, 2012 experienced the highest number of publications with ten articles after a limited number of publications from 2003 to 2011. However, this number has dropped to two papers which were published in 2013. Compared to other quality improvement methodologies, and to articles on LSS in other industries such as healthcare, this number of articles is quite low, but nevertheless indicates an incremental growth trend. The comparatively low volume of articles indicates that there is a crucial need for more research into LSS implementation in the manufacturing sector, especially as LSS implementation is growing rapidly in popularity in this area, as evidenced by leading corporations citing LSS as a cornerstone philosophy for their businesses. However, this low number of LSS publications is still sufficient to conduct a systematic literature review in the field of LSS. This is because there is not an agreed minimum number of papers that should be reviewed when conducting a systematic review. The authors also noticed that a number of systematic reviews have been published in academic journals and a few number of papers have been reviewed by researchers as part of the systematic literature review. For instance, Medeiros et al. (2011) have systematically reviewed 14 papers which met their research inclusion criteria. 3.2 Distribution of publications across the different countries Analyzing the findings regarding the distribution of publications of LSS in the manufacturing sector across the different countries has resulted in 11 countries as shown in Figure 4. The USA has got the largest number of publications with 48.6 percent (18 papers) of the total publication. The UK and India have come in second place with almost a quarter of the number of US publications (four papers). Other countries such as Taiwan, China, Iran, etc., were found to be far behind the USA. 3.3 LSS paper themes This section of the paper will present the most common themes using tables and figures to illustrate the results. In addition, LSS papers were found to have included different contents and themes as shown in Table IV. 3.3.1 Benefits of successful LSS implementation in the manufacturing sector. A review of 37 LSS papers showed that 19 case studies had been published in the manufacturing sector in seven different countries, which are: the USA, the UK, India, NumberofArticles 10 12 0 2 4 6 8 Year of Publication Growth of LSS Publication in Manufacturing Sector 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 Figure 3. Growth of LSS publications in the manufacturing sector 672 BPMJ 21,3 DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  the Netherlands, Chinaand New Zealand – these are shown in Table V. The table also shows factors outside LSS as well as other tools and techniques that helped these organizations with successful implementation. The analysis of LSS benefits in the manufacturing sector in Table V has resulted in more than 50 benefits being identified in 19 case studies. The top ten benefits cited in the papers are: (1) increased profits and financial savings; (2) increased customer satisfaction; (3) reduced cost; (4) reduced cycle time; (5) improved key performance metrics; (6) reduced defects; (7) reduction in machine breakdown time; (8) reduced inventory; (9) improved quality; and (10) increased production capacity. Other soft benefits such as identifying different types of waste, development in employee morale toward creative thinking and reduction in workplace accidents as a result of housekeeping procedures also appeared in a number of cases. In addition, analyzing the type of industry where the most LSS cases emerged showed that there is no common industry. This means that industry types vary from large industries such as aircraft manufacturing and proprietary military products to Distribution of LSS Publications Across the Different Countries USA 48.6% (18 Papers) UK 10.8% (4 Papers) India 10.8% (4 Papers) Malaysia 8.1% (3 Papers) Australia 5.4% (2 Papers) Iran 2.7% (1 Paper) The Netherlands 2.7% (1 Paper) Taiwan 2.7% (1 Paper) New Zealand 2.7% (1 Paper) China 2.7% (1 Paper) Sweden 2.7% (1 Paper) Figure 4. Distribution of publications in LSS in the manufacturing sector across different countries Theme No. of papers Benefits (case studies) 19 Motivation factors 23 Impeding factors 12 Limitations 12 Table IV. LSS papers – themes in the manufacturing sector 673 A systematic review of Lean Six Sigma DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  Industry Reasonsbehind implementingLSSToolsandtechniquesBenefits Homefurnishing(USA) (Chakravortyand Shah,2012) Tochangetheoperationtoshow positiveresults Toimproveemployees’morale Toimproveproductqualityand manufacturingoperations SIPOC,VSM,C&Eanalysis, SMED,DOE,ANOVA, Paretoanalysis,Poka-yoke Improvementofmanufacturingoperationperformance Improvementofteammembers’skills Improvementofproductioncapacity Reductionincost,cycletime,customerreturnsandinventory Reductioninvariationandwastefromoperation Aircraftmanufacturing company(USA) (Akbulut-Bailey etal.,2012) Toimprovethecompetitiveposition inthemarket Toincreasethebottomlineby reducingthecostofoperations C&Eanalysis,Kanban, Jidoka Saleswentfrom$30mto$205m/year Reductionininventory,waste,productioncost,labor timeandcycletime Significantimprovementinquality Increaseinproduction,customersatisfactionandmarketshare Proprietarymilitaryproducts (worldwide)(Pickrelletal., 2005) Toreduceproductioncost Toreducecycletime,customer returnsbacklog,supportlaborand inventory Toincreaseproductioncapacity SIPOC,C&Eanalysis,DOE, SPC,processmapping, brainstorming 50%overallreductionintotalcost 53%reductionincycletime 82%reductionincustomerreturnsbacklog 32%reductioninsupportlaborrequired 52%increaseinproductioncapacity 50%reductionininventory Deeperunderstandingofproductionprocess Compressorairfoilfactory (USA)(Hardemanand Goethals,2011) Toimprovetheefficiencyofthe shimmingprocess Toenhancethequalityoftheproduct C&Eanalysis,FMEA94%reductioninproductdefects Increasedsigmavaluefrom0.868to3.207 Eliminationofunnecessarytoolingandworkareacleanedup Effectivestoragesystemhasbeencreated Significantimprovementintheprocessefficiency Reductionintheamountofproductscrapped Smallengineeringcompany (UK)(Thomas etal.,2009) ToexaminethevalidityofanewLSS integratedapproachthathasbeen developedbytheresearchersinthe study 5S,VSM,TPM,DOE,QFD, SPC Apotentialsavingovertheyearof£29,000 IncreaseincellOEEfrom34to55% Increaseinproductionby31%perhourfrom15to25pph.Thisadded 2,800additionalpartsperannum 12%reductionintheuseofenergyperannum Reductioninequipmentdowntimefrom5to2% Abilitytocompeteinthemarkethasincreasedsignificantly Increasedcustomersatisfaction Companyproductportfolioshiftedtoahigher-valuemarketsector Increasedawarenessofstatisticaltechniquesforproblemsolving (continued) Table V. The benefitsof successful implementation of LSS in the manufacturing sector 674 BPMJ 21,3 DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  Industry Reasonsbehind implementingLSSToolsandtechniquesBenefits PCBmanufacturer(China) (LeeandWei,2009) Todiscovervariationandwaste causesintheICTmoldchange processandreduceit Toreducethenumberofirregularpin pointsonapinboard Processmapping,C&E analysis,ANOVA,FMEA, 5S,TPM Increaseinproductionutilizationratefrom66.77to92.71%within 3months Increaseinthroughputby22,500PCBsperday Significantreductioninfixturesearchtime,anaverageof 4.73-1.53min. Decreaseinerroneouspinsfrom72to11.5%within3months,andto 1.8%within6months Developmentofaplanforfuturemaintenanceandequipment replacement Tiremanufacturingcompany (India)(Bhuiyanetal.,2006) Toreducedefectsoccurringin production VSM,5S,C&Eanalysis, root-causeanalysis Reductionindefectivetiresintotalmonthlyproductionfrom22-25to 15%withinthefirstmonth Rotaryswitches manufacturing(India) (Vinodhetal.,2012) Toreducedefectsoccurringin productionandstreamlineprocess flow Toincreasecustomersatisfaction Toreducescrapandreworkcost Paretochart,C&Eanalysis, VSM,controlcharts,DOE, Kanban,5S,Poka-yoke 10%reductioninproductdefects 10%reductionindefectsineachstageofkeyperformancemetrics 7%increaseinfirst-timeyield(FTY) Bettercustomersatisfaction Reductioninmachinebreakdowntime Increaseinprofit Morethan50%reductioninworkinprocess(WIP)inventory Identified7typesofwaste Increasedemployeemoraletowardcreativethinking Touchpanelmanufacturing (Taiwan)(ChenandLyu, 2009) Toimprovethequalityofthetouch panel Toincreasecustomersatisfaction regardingproductpriceandquality Toimproveyieldrate VOC,C&Eanalysis,SIPOC, ANOVA,Paretoanalysis, SPC,DOE,currentstate map Reductionindefectsfrom32.4%tolessthan15% Reductioninproductcostandincreaseincustomersatisfaction DevelopmentinLSSmembers’experienceandknowledgeof advancedstatisticaltrainingsuchasdesignofexperiments(DOE) sincetheDOEisakeysuccessfactorduringtheimprovementphase TheprocesscapabilityanalysisofthestampprocessyieldedaCpkof 2.34andPpkof2.25,implyingtheprocesshasalreadyreachedaSix Sigmaqualitystandard (continued) Table V. 675 A systematic reviewof Lean Six Sigma DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  Industry Reasonsbehind implementingLSSToolsandtechniquesBenefits Automobileaccessories manufacturing(India) (Kumaretal.,2006) Toreducedefectsoccurringinthe finishedproduct Towincustomerloyalty Toenhancethebottomline Toreduceworkinprocessinventory Toreducecostofscrapandrework Currentstatemap,5S, TPM,VOC,Paretoanalysis, brainstorming,DOE, controlcharts,FMEA Significantfinancialsavingof$46,500peryearduetodefectreduction Reductioninmachinedowntimefrom6to1% Over$33,000savingperyeardueto25%reductioninprocess inventory $20,000maybesavedduetothereductioninworkplaceaccidentsasa resultofhousekeepingprocedures Keyperformancemetricshaveimprovedsignificantly(e.g.defectperunit (DPU),processcapability,first-timeyield(FTY),etc.). Increasedoverallequipmenteffectiveness(OEE)andthustheoverall plantefficiency(OPE) Reductionincustomercomplaints,machinesetuptime,workplace accidents Totalsavingsofaround$140,000peryear Automotivevalves manufacturing(India) (Vinodhetal.,2011) ToimproveFTR Toreducedefectsoccurringinthe finishedproductandincrease customersatisfaction SIPOC,brainstorming, VOC,currentstatemap,5S, VSM,Paretochart,C&E analysis,controlchart, DOE,Kanban Customersatisfactionhasincreased Theimprovementoffirst-timeright(FTR)percentagefrom98.2to 99%wouldsave28,000valvespermonthfromrejection Significantsavingshavebeenachieved Reductioninmachinebreakdowntime,inventory,changeovertime(C/ O)by25%,andinmanufacturinglead timeby18.53% 50%decreaseinDPU 17.64%increaseinOEE Reductioninannualmovementofmaterialsfrom2,040to1,300miles; hence,thematerialmovementcosthasreducedfrom$187,298to $103,886peryear Industrialcleaning equipmentmanufacturing (USA)(FranchettiandYanik, 2011) Toreducecostby15%,reducewaste andprotectrevenue Toachievecompetitiveadvantagein qualityandmarketshare Toincreasecapacityby10% CTQanalysis,SIPOC, brainstorming,VSM,Pareto analysis,root-cause analysis,FMEA,Kanban $660,000reductionincostperyear 50%reductioninworkcells (continued) Table V. 676 BPMJ 21,3 DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  Industry Reasonsbehind implementingLSSToolsandtechniquesBenefits Armamentsproducts(USA) (Corbett,2011) Togainfinancialbenefitsby reducingcostandcycletime 5S,TPM,VSM,process Map,C&Eanalysis,XY matrix,FMEA,capability analysis,SPC,ANOVA, DOE,controlcharts,root- causeanalysis Improvementsof91%inquality,70%incost,67%indelivery,84% inrisk $3bncostbenefitfrom2001to2007 WonMalcolmBaldrigeNationalQualityAward(MBNQA) Buildingproducts(New Zealand)(Corbett,2011) Tobuildnichemarket Togainfinancialbenefitsby reducingcostandcycletime 5S,TPM,VSM,process map,C&Eanalysis,XY matrix,FMEA,capability analysis,SPC,ANOVA, DOE,controlcharts,root- causeanalysis $28mannualsavingfrom2002to2007 WonBusinessExcellenceAward(BX) HoneywellInternationalInc. (USA)manufacturing differentproductsfrom aerospaceproductsto electronicmaterials(William andWillie,2003) Toreducefinalproductsalepricesby 50% Toimproveproductivitycapacityby double Togrowthebusinessto$1mand $250thousandsinimpact Toimprovecashflow Processmapping,C&E analysis,FMEA,SPC,5S andmistakeproofing $3binfinancialbenefitsfrom1995to2011 $1.2bgainsin2002asaresultofwastereduction Cycletimereducedfrom12to10days Producttraveldistancereducedsignificantlyfrom300to14Km Reductioninmanufacturingcostby50% Largevalveremanufacturing (USA)(Kucner,2009) Toimprovequality,reducecostand shortencycletimeinthecarrier’s designandmanufacture 5S,VSM,kaizen, brainstorming,root-cause analysis Throughputofremanufacturinglinenearlytripled Averagecomponentleadtimewasreducedfrom180to40days, overtimewaseliminated,andcostandschedulegoalswereregularly achieved Qualityandcommunicationimprovedsignificantly Automotiveelectronic componentassemblyplant (Malaysia)(Yietal.,2012) Toreduceproductioncost Toreducedefectsinproduction Toreducelosses($300,000)from electroniccomponentloss C&Eanalysis,Paretochart, brainstorming,5S,VSM, Poka-yoke,SPC 18%reductioninelectroniccomponentlossesintheplantfrom$7,680 to$6,400within16weeksoftheimprovementphase Significantreductioninproductioncost (continued) Table V. 677 A systematic reviewof Lean Six Sigma DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  Industry Reasonsbehind implementingLSSToolsandtechniquesBenefits Printingsampleboards manufacturing(USA)(Roth andFranchetti,2010) Tomeettheprojectedyearlydemand of200,000boards(recently143,400 boards/year)byreducingwasteinthe processandincreasingproduction capacitythroughwastereduction Toincreaseclients’competitive advantageintheprintingindustry Paretochart,E-Kanban system,SOP,checksheet Customerdemandhasbeenmetbycreatingbetterprocessesand improvedproductcost Laborcostminimizedbyestablishingtheoptimalnumberof employees Reducethenumberofdefectsintheproductionprocess Qualityoffinishedgoodshasbeenimproved Gasesandengineering organization(USA)(Waite, 2013) Tobeleanerandmoreefficient Toeliminatenon-valueadded activities Toincreaseefficiencyand standardization Toeliminateproductsandother materialsthatarenolongerused Currentstatemap, spaghettidiagram,VSM, 5S,Poka-yoke Eliminated1,163manhoursofannualnon-valueaddedwalkingfrom acylinder-fillingprocessatonefacility Productivityincreasedby18-48%,dependingonthesite Variableproductioncostdecreasedby10-35%,dependingonthesite Increasedemployeemoraleacrosstheboard Table V. 678 BPMJ 21,3 DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  home furnishing manufacturing.Hence, authors argue that this variation illustrates the success of LSS in all industry types. Table V shows the most common tools to emerge from the cases. The top five common tools are: (1) C&E analysis (13 case studies); (2) VSM (12 case studies); (3) 5S (11 case studies); (4) DOE (eight case studies); and (5) Pareto chart (seven case studies). These tools and techniques have been used under the DMAIC method in almost all cases, as DMAIC is the solid basis for LSS implementation (Chakravorty and Shah, 2012). The reason behind the common use of these tools and techniques in most cases is the simplicity of these tools, especially the top three tools as they are straightforward and do not contain any statistical equations or formulas. Thomas et al. (2009) argued that organizations avoid deploying Six Sigma as a result of the heavy statistic and the complexity of the tools and techniques. In addition, management and employees become frightened when these tools are discussed. Hence, most of the organizations, especially in the UK and Europe, would prefer to deploy Lean tools, as they are non- statistical tools. The authors observed a rich seam of publications stating LSS benefits in the manufacturing sector, but no studies were found reporting a failure of LSS implementation. There may be many reasons for this: businesses are presumably not keen to spend time and effort preparing studies for publication that only demonstrate failure, or it may be bias in the selection of articles for publication by the various journals, who only want to report successes. The fact remains that this is a significant omission: publication of detailed analysis of failed implementations or projects would be of great benefit to those businesses contemplating LSS implementation in the future. 3.3.2 Motivation factors for LSS implementation in the manufacturing industry. There are 17 different factors that motivate companies in the manufacturing sector to apply LSS in their organizations, as cited in Table VI. These factors have been extracted from 23 papers; most of them are case studies. Figure 5 shows top five motivation factors and the number of published papers in each factor. In most of the cases the common reasons for deploying LSS are, to change the competitive position in the market or to stay in the competition in the international market, to increase customer satisfaction, attraction and loyalty, and to improve product quality and manufacturing operations. Other factors are to increase the bottom line and to reduce the cost of quality such as cost of poor quality, production cost and so on. The real benefits gained in the manufacturing sector motivate other organizations in different sectors such as services and healthcare to implement LSS. Motivation factors are one of the most common themes that appeared in LSS literature. A number of factors have appeared in few studies: for example the implementation of LSS could improve employees’ morale. This factor needs to be supported by more research to explore the relation between LSS implementation and the human factor. Thomas et al. (2009) argued that reducing machine downtime is a big step toward reducing lead time. Hence, organizations save hard cash to the bottom line by reducing 679 A systematic review of Lean Six Sigma DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  Motivation factors References Tochange operations to show positive results Chakravorty and Shah (2012), Thomas et al. (2009) To implement continuous improvement strategies Chakravorty and Shah (2012) To improve employees’ morale Chakravorty and Shah (2012), Waite (2013) To improve product quality and manufacturing operations Chakravorty and Shah (2012), Thomas et al. (2008, 2009), Chen and Lyu (2009), Pickrell et al. (2005), Hardeman and Goethals (2011), Franchetti and Yanik (2011), Richard (2008) To change the competitive position in the market or to stay in the competition in the international market Chakravorty and Shah (2012), Maleyeff et al. (2012), Hilton and Sohal (2012), Thomas et al. (2008), Franchetti and Yanik (2011), Akbulut-Bailey et al. (2012), Corbett (2011), Roth and Franchetti (2010), Bossert (2013) To increase the bottom line Kumar et al. (2006), Thomas et al. (2008), Akbulut-Bailey et al. (2012), Corbett (2011), William and Willie (2003), Snee (2010) To reduce cost (cost of poor quality/production cost) Thomas et al. (2009), Chen and Lyu (2009), Kumar et al. (2006), Pickrell et al. (2005), Waite (2013) To reduce customer returns backlog or support labor Franchetti and Yanik (2011), Yi et al. (2012), Kumar et al. (2006) To increase production capacity by reducing machine breakdown time Thomas et al. (2009) To improve process efficiency Hardeman and Goethals (2011), Arther and George (2004), Roth and Franchetti (2010), Waite (2013) To discover causes of variation and waste in the process Lee and Wei (2009), Roth and Franchetti (2010) To enhance business sustainability Maleyeff et al. (2012), Pickrell et al. (2005) To reduce defects in production Bhuiyan et al. (2006), Vinodh et al. (2012), Kumar et al. (2006), Richard (2008), Yi et al. (2012) To increase customer satisfaction, attraction and loyalty Vinodh et al. (2012), Chen and Lyu (2009), Kumar et al. (2006), Franchetti and Yanik (2011), Arther and George (2004), Richard (2008), Snee (2010), Roth and Franchetti (2010) To improve product/process yield rate Chen and Lyu (2009), Thomas et al. (2008) To reduce time (cycle time, lead time, etc.) Pickrell et al. (2005), Corbett (2011), William and Willie (2003), Snee (2010) To reduce inventory Kumar et al. (2006), Pickrell et al. (2005) Table VI. Motivation factors for LSS implementation in the manufacturing industry Motivation Factors for LSS implementation in Manfacturing Industry To change competitive position in the market To increase customer satisfaction To improve product quality To increase the bottom line To reduce cost NumberofArticles 10 9 8 7 6 5 4 2 3 1 0 Figure 5. Top five motivation factors for LSS implementation in the manufacturing sector 680 BPMJ 21,3 DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  machine downtime. Thisview is supported by many studies, for instance Vinodh et al.’s (2012) case study on rotary switches manufacturing in India, Kumar et al.’s (2006) case study on automobile accessories manufacturing in India and many others. In addition, authors observed that most of the organizations have been motivated to apply LSS to increase customer satisfaction or to reduce costs and to save hard cash to the bottom line. However, these organizations may not be aware of all the LSS possibilities for improvement in the different departments in their organizations. This illustrates the lack of organizations’ awareness of LSS benefits. Authors argue that there is a strong relation between motivation and benefit as lack of motivation leads to fewer benefits. An organization’s motivation can be increased by the use of other companies’ success stories and understanding their motivation factors for deploying LSS, as well as the benefits they have gained from LSS. 3.3.3 Limitations of LSS in the manufacturing sector. Many authors have argued that there are a significant number of limitations in LSS methodology. Nine fundamental limitations were addressed in 12 papers as cited in Table VII. These limitations can be a rich area for future research. According to Table VII, the top five limitations of LSS in the manufacturing sector are: (1) The absence of clear guidelines for LSS in early stages of implementation. (2) Lack of LSS curricula. (3) Lack of understanding of the usage of LSS tools and techniques. (4) Lack of a roadmap to be followed – which strategy first? (5) The limited number of practical applications of LSS integrated framework. Regarding the absence of a roadmap for LSS implementation, especially in the early stages, Kumar et al. (2006) argued that practitioners need a clear guide for the direction of the early stages: which strategy should come first, Lean, Six Sigma or LSS, and what tools in the toolbox should be used first. Furthermore, Kumar et al. (2006) observed that there is no clear understanding of the usage of LSS tools and techniques in manufacturing organizations. Hilton and Sohal (2012), Breyfogle (2008) and Salah et al. (2010) argued that more standardized and more robust LSS curricula are needed in order to leverage learning in organizations. Hence, developing curricula for LSS has emerged in this paper as an area for future research. 3.3.4 Impeding factors for LSS implementation in the manufacturing sector. While organizations and practitioners in the manufacturing sector are applying LSS, they face a number of complex impeding factors. These factors or challenges as cited by some authors in 12 papers are presented in Table VIII. The last theme explored in this paper was the impeding factors for successful implementation of LSS in the manufacturing sector. The implementation of any CI program must overcome impediments, and it is valid to discuss some of the impeding factors that faced the manufacturing sector while they were implementing their LSS programs. Table VIII depicts impeding factors to LSS implementation reported by the manufacturing sector. The top six impeding factors reported are: (1) time-consuming; (2) lack of resources; (3) unmanaged expectations; 681 A systematic review of Lean Six Sigma DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  (4) lack ofawareness about LSS benefits in business; (5) lack of training or coaching; and (6) employee reaction towards a new business strategy. Other factors have emerged by some authors such as convincing the top management about the benefits of LSS in business. This factor is due to a belief by top managers that investment in quality improvement programs is no more than wasting money and increasing production cost (Kumar et al., 2006). Authors argue that from the results of reviewed case studies, this view cannot be true. Organizations gained massive savings to their bottom line as a result of investment in quality improvement programs. Researchers have found that a number of factors emerged in studies by Timans et al. (2012), Thomas et al. (2008), Maleyeff et al. (2012), Chakravorty and Shah (2012) and Richard (2008). Lack of tangible results is one of the impeding factors reported by Timans et al. (2012). Researchers argue that this factor cannot be a true impediment, Limitations Description Reference No globally accepted standards for certification Some companies have adapted the LSS certification system for themselves. This causes confusion and lack of trust in the industry Laureani and Antony (2012), Breyfogle (2008) Lack of emphasizing of accurate measurements for LSS implementation in literature Timans et al. (2012) suggested a performance measurement system that is based on previous literature and international quality awards such as MBNQA, AQA and EQA Chakravorty and Shah (2012) The limited number of practical applications of LSS integrated framework More case studies are needed to examine the integrated framework of LSS in the manufacturing sector Vinodh et al. (2012), Chen and Lyu (2009) Lack of understanding of the usage of LSS tools and techniques Kumar et al. (2006) observed that there is no clear understanding of the usage of LSS tools and techniques in organizations Kumar et al. (2006), Thomas et al. (2008), Pepper and Spedding (2010) The absence of clear guidelines for LSS in early stages of implementation Kumar et al. (2006) argued that practitioners need clear guidelines for the direction of the early stages, such as which strategy should come first, Lean, Six Sigma or LSS and which tools should be used first Kumar et al. (2006), Vinodh et al. (2011), Thomas et al. (2008), Pepper and Spedding (2010) The lack of LSS standardization curricula Standard LSS curricula are needed in order to leverage learning in organizations (Salah et al., 2010) Hilton and Sohal (2012), Breyfogle (2008), Salah et al. (2010) Lack of innovation in LSS projects This limitation is as a result of the implementation of simple tools for improvement such as 5S, waste removal, etc. (Thomas et al., 2008) Thomas et al. (2008) Lack of a roadmap to be followed – which strategy first? This limitation can be resolved by adapting the roadmaps available in literature, depending on specific organizational needs (Snee, 2010) Snee (2010), Kumar et al. (2006) The absence of a sustainability framework for LSS It is important to put in place a plan for sustaining the results before the start of the project implementation phase. This is a serious limitation too. How can an LSS initiative be sustainable? Snee (2010) Table VII. Limitations of LSS in manufacturing sector 682 BPMJ 21,3 DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  Factors Description References Difficultiesin teaching statistical methods to some of the team members Many LSS team members are not familiar with statistics (Chakravorty and Shah, 2012). To solve this problem, authors suggest using LSS learning games to make complex tools and techniques easy to understand Chakravorty and Shah (2012), Thomas et al. (2009) Time-consuming One of the challenges that always faces executives in companies is the time it takes for LSS project implementation (Richard, 2008) Richard (2008), Pepper and Spedding (2010), Smith (2003), Bossert (2013) Internal resistance Timans et al.’s (2012) survey results in SMEs showed that 54% of the respondents mentioned internal resistance as a barrier to LSS implementation Timans et al. (2012), Antony et al. (2003) Lack of resources Richard (2008) stated that implementing LSS projects requires using resources. These resources are not always available in the organization; hence, this is undoubtedly a big challenge in LSS implementation Timans et al. (2012), Thomas et al. (2008), Richard (2008) Changing business focus Timans et al.’s (2012) survey results in SMEs showed that 43% of the respondents mentioned changing business focus as a barrier to LSS implementation Timans et al. (2012) Lack of leadership Timans et al.’s (2012) survey results in SMEs showed that 39% of the respondents mentioned lack of leadership as a barrier to LSS implementation Timans et al. (2012), Antony et al. (2003) Poor selection of projects This can cause wasting of time, effort and resources. It also causes skepticism among many people and might kill the initiative eventually Timans et al. (2012) Lack of tangible results All the reviewed case studies showed many positive and tangible results such as savings in bottom line, quality improvement and so on. However, Timans et al. (2012) argued that in some cases, the company does not get any positive results from the deployment of LSS and this impedes the company from completing LSS projects Timans et al. (2012) Lack of training or coaching Thomas et al. (2008) stated that many companies have failed in LSS implementation as a result of the lack of training and knowledge of LSS tools and techniques Timans et al. (2012), Breyfogle (2008), Thomas et al. (2008) Unmanaged expectations In many cases, expectations about results vary between senior managers and practitioners. This should be addressed from the very early stages of LSS implementation (Thomas et al., 2008). In some cases, organizations cannot achieve the expected benefits to the bottom line (Richard, 2008) and this definitely leads the whole project to failure. Hence, the organization wastes money, time and effort with no specific improvement Timans et al. (2012), Thomas et al. (2008), Richard (2008) Competing projects This relates to the selection of projects, which may be competing for implementation of resources. Managers should use appropriate criteria to select the most beneficial projects, as well as some project selection tools and techniques such as brainstorming, Critical to Quality (CTQ), focus group, Kano analysis and so on Timans et al. (2012) (continued) Table VIII. Impeding factors for LSS implementation in the manufacturing sector 683 A systematic review of Lean Six Sigma DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  because around 50tangible results have been extracted from reviewed papers in the manufacturing sector. For instance, 50 percent of the reviewed papers stated significant increases in savings and bottom line, up to $3bn in some cases, decreased cycle time significantly by an average of 25-50 percent (as stated by Kucner, 2009, in navy- commissioned nuclear aircraft carrier in the USA, lead time was reduced from 180 to 40 days). A number of cases cited reduction in inventory and waste in processes as well as reduction in the percentage of production defects. It can, therefore, be argued that it is possibly a lack of visible results rather than a lack of tangible results that is at issue here. Many authors such as Richard (2008) and Pepper and Spedding (2010) have argued that the implementation of LSS projects in an organization often takes too long and this is one of the challenges facing executives in organizations. Master Black Belts spend around six months or more on each LSS project and LSS projects usually take months to be completed (Smith, 2003). However, Snee (2010) argued that the implementation of LSS projects should not take more than three to six months, and this is one of the characteristics that differentiate LSS from other improvement initiatives. From the researchers’ point of view, there is a clear variation in authors’ opinions toward the time taken for LSS project execution. This variation could be as a result of differences in culture, LSS awareness, level of training, etc., as all these factors affect the time required for LSS implementation. Future research such as an empirical study is needed to address this gap in the literature. Factors Description References Poor employee relationships This can affect LSS implementation. It is important for LSS employees to have good relations with each other to enhance the probability of project success and make for an effective working environment Timans et al. (2012) National regulations Both lack of regulation and overregulation put pressure on companies and prevent them being able to operate effectively within the global market (Maleyeff et al., 2012) Maleyeff et al. (2012) Employee attitude toward a new business strategy In many cases, employees think that new business strategies could put them at risk of losing their jobs if their performance is seen to be under the required level Vinodh et al. (2012), Kumar et al. (2006), Antony et al. (2003) Convincing top management Top management often believe that investment in quality improvement programs is no more than wasting money and increasing production costs (Kumar et al., 2006) Vinodh et al. (2012), Kumar et al. (2006) Lack of awareness about LSS benefits in business This is one of the top challenges facing businesses, but can be tackled through training and education, as well as by getting lessons from previous successful stories of other organizations (Snee, 2010) Kumar et al. (2006), Thomas et al. (2008), Snee (2010) Poor organizational structure Thomas et al. (2008) believe that problems in organizational structure such as financial and technical problems can limit the success of implementation of LSS Thomas et al. (2008) Lack of skills required for successful deployment Lack of skills such as managerial, technical, statistical, etc., can be a significant barrier to LSS implementation. Without the availability of skilled members, driving a new culture into the organization could be impossible (Thomas et al., 2008) Thomas et al. (2008), Franchetti and Yanik (2011) Table VIII. 684 BPMJ 21,3 DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  4. Gaps inthe current literature on LSS and agenda for future research The following gaps have been identified by the authors in the current literature on LSS. These gaps have been grouped and prioritized as follows: (1) Lack of a holistic approach to CI. A number of organizations select a particular approach to CI rather than taking a holistic approach to CI. For instance, some organizations choose Kaizen as its primary CI methodology, some other organizations utilize Lean as its primary CI methodology and some others choose Six Sigma as the primary CI methodology. However, there is no systematic framework currently available in the literature which guides organizations to choose a suitable CI for a given problem or scenario. (2) Lack of standardization for certification. Although a number of companies provide training and certification on LSS, the authors would like to highlight the point that there is a clear lack of standardization for both training and certification. There is a need for the standardization of LSS curriculum for manufacturing companies (both large- and small- and medium-sized enterprises), service industries, public sector organizations and finally third sector organizations. The certification requirements (number of projects to be completed, savings generated from the project, etc.) vary significantly from one provider to another and this causes major issues in terms of developing the world class practice for LSS. (3) Linking LSS with learning organization. Although a large number of companies have been implementing LSS as a core strategy for CI, many of them have failed to link LSS with learning organization. Some aspects of organizational learning need to be addressed such as social aspects, cultural aspects of human action, cognitive aspects, technical aspects of the work, change aspects, etc. This topic is very important for people to learn from mistakes, especially when projects fail. Failed projects are a rich source of learning, and publishing failure stories can definitely guide future research efforts in the field. For instance, at what point a LSS Black Belt and the project champion terminate a project and what are the critical factors for termination of LSS projects. (4) LSS for SMEs. Although a large number of big organizations are deploying LSS, research has shown that very few empirical studies have been published on LSS and its current status in the context of SMEs. A number of scholars have published case studies of LSS in the context of SMEs. However, the authors would like to accentuate the point that SMEs do need a roadmap for implementing LSS and this is clearly lacking in the existing literature. Moreover, there is a desired need for the development of a LSS toolkit customized for SMEs. In addition to this, very little research has been carried out showing what kind of infrastructure is required for making LSS deployment successful in SMEs. Other research gaps identified by the authors include: • LSS and its link to innovation as a key driver for organizations to survive, grow and sustain competitiveness. 685 A systematic review of Lean Six Sigma DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  • LSS forenhancing supply chain performance and how long-term relationships with suppliers can improve productivity, quality and customers’ satisfaction. • LSS and environmental management system (Green LSS) to explore the relation between LSS and the environment. This will be helpful for environmental professionals to guide them on how to connect their work with LSS activities to generate better environmental and operational results. • LSS for public sector organizations, e.g. healthcare, education, councils, police force and so on. • LSS for high-value and low-volume environment which have not been fully understood and correctly applied such as the deployment of LSS in the aerospace manufacturing industry. • LSS Readiness Index Model to assess the readiness of an SME to embark on a LSS journey. • Leadership and its impact on successful deployment of LSS. 5. Conclusion There is a noticeable increase in the popularity of LSS and level of LSS deployment in the industrial world especially in large organizations in western countries such as the USA, the UK and the Netherlands, and in some SMEs in developing countries such as India. There are important themes cited in this paper, which are: benefits, motivation factors, limitations and impeding factors. The application of LSS methodology in 19 case studies in the manufacturing sector has resulted in significant benefits in the manufacturing sector. The paper also explored the most commonly used tools and techniques in the case studies that were included in this research. Interestingly enough, the use of Lean tools and techniques such as VSM, 5S, etc., was more common in most cases, as these tools and techniques are non-statistical, unlike Six Sigma tools and techniques, while the use of the Six Sigma toolkit was more familiar in the American manufacturing sector than in Europe. In addition, many gaps in the current LSS literature have been identified such as the absence of a sustainability framework of LSS and a lack of research in the relation between LSS and organizational learning. Therefore, a future research agenda for LSS has been developed in this research. The key findings of the systematic literature review can be used by senior managers before they embark upon the LSS journey. Moreover, the findings from the research can also act as a set of guidelines (barriers, benefits, motivation, etc.) in the introduction development and implementation of LSS. This study, as other previous studies, has limitations. One limitation is the small number of searched papers. The size of the search was due to the inclusion and exclusion criteria that were developed by the researchers to include only top-ranking journals and specialist journals in the field. Another limitation is the narrowing of the research to the manufacturing sector only – however, manufacturing is the specialist area of the researcher, and therefore an area of expertise that has enabled a greater depth of knowledge to be applied to this study. Other systematic reviews will therefore need to be conducted in the service sector, construction sector and healthcare sector in the future. 686 BPMJ 21,3 DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  Wang, M.-T., Wan,H.-D., Chen, H.-Y., Wang, S.-M.A., Huang, S.-C.A. and Cheng, H.-Y.L. (2012), “Six Sigma and Lean Six Sigma: a literature review and experience in Taiwan”, Conference of International Foundation for Production Research-Asia Pacific Region, Patong Beach, Phuket, December 2-5. William, H. and Willie, K. (2003), “The Honeywell experience”, ASQ Six Sigma Forum Magazine, Vol. 2 No. 2, pp. 34-37. Womack, J.P. and Jones, D.T. (2003), Lean Thinking: Banish Waste and Create Wealth in Your Corporation, Free Press, New York, NY. Womack, J.P. and Jones, D.T. (2005), “Lean consumption”, Harvard Business Review, Vol. 83 No. 3, pp. 58-69. Womack, J.P., Jones, D.T. and Roos, D. (1990), The Machine that Changed the World, Rawson Associates/Macmillan Publishing Company, New York, NY. Yi, T.P., Feng, C.J., Prakash, J. and Ping, L.W. (2012), “Reducing electronic component losses in lean electronics assembly with Six Sigma approach”, International Journal of Lean Six Sigma, Vol. 3 No. 3, pp. 206-230. Zhang, Q., Irfan, M., Khattak, M.A.O., Zhu, X. and Hassan, M. (2012), “Lean Six Sigma: a literature review”, Interdisciplinary Journal of Contemporary Research in Business, Vol. 3 No. 10, pp. 599-605. About the authors Saja Ahmed Albliwi is a PhD Candidate in the School of Management and Languages, Heriot- Watt University, UK. She got her Master of Science in 2011 in Strategic Project Management from the School of Management and Languages, Heriot-Watt University, UK. She got her Bachelor of Science in Housing and Home Management from the King Abdulaziz University, Saudi Arabia in 2007. Currently she is working as a Teacher Assistant at the King Abdulaziz University and she was awarded a scholarship from the same university for her PhD study. She presented in ICMR conference in September 2013 and she has published a paper in IJQRM in September 2014 in the topic of Lean Six Sigma. Currently, she is working on a journal article publication and a conference paper in the field of Lean Six Sigma. She has taught classes in Lean Six Sigma for postgraduate students in the University of Strathclyde. She is also a member of the American Society for Quality and EurOMA. Her current research interests are centered in the field of Lean Six Sigma, quality management, operation management and continuous improvement. Saja Ahmed Albliwi is the corresponding author and can be contacted at: s.albliwi@hotmail.co.uk Professor Jiju Antony is recognized worldwide as a Leader in Six Sigma methodology for achieving and sustaining process excellence. He founded the Centre for Research in Six Sigma and Process Excellence (CRISSPE) in 2004, establishing first research centre in Europe in the field of Six Sigma. He is a Fellow of the Royal Statistical Society (UK), Fellow of the Institute for Operations Management (UK), Fellow of the Chartered Quality Institute (CQI), Fellow of the American Society for Quality (USA) and a Fellow of the Institute of the Six Sigma Professionals. He has recently been elected to the International Academy of Quality and is the first one to be elected from Scotland and the fourth person from the UK. He is a Certified Master Black Belt and has demonstrated savings of over ten million pounds to the bottom line of several organizations around Europe. He has a proven track record for conducting internationally leading research in the field of Quality Management and Lean Six Sigma. He has authored over 270 journal and conference papers and six text books. He has published over 75 papers on Six Sigma topic and is considered to be one of the highest in the world. He was the past Editor of the International Journal of Six Sigma and Competitive Advantage and is currently serving as the Editor of the first International Journal of Lean Six Sigma launched in 2010 by Emerald Publishers. He is the founder of the first international conference on Six Sigma in the UK back in 2004 and is also the founder of the first international conference on Lean Six Sigma for higher education. He has been a keynote speaker for various conferences around the world and is a regular speaker for 690 BPMJ 21,3 DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)
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  ASQ’s Lean SixSigma Conference in Phoenix, USA. Professor Antony has worked on a number of consultancy projects with several blue chip companies such as Rolls-Royce, Bosch, Parker Pen, Siemens, Ford, Scottish Power, Tata, Thales, Nokia, Philips, GE and a number of small- and medium-sized enterprises. Sarina Abdul Halim Lim is a PhD Candidate in the School of Management and Languages, Heriot-Watt University, UK. She holds her Master of Science in Quality and Productivity Improvement at the Mathematical Centre, University of National Malaysia and Bachelor of Science in Mathematics, University of Technology Malaysia. She presented and published in several conferences for the past few years and currently working on the journal article publication in the field of statistical process control. Currently she is working at the University of Putra Malaysia and she was awarded a scholarship from the Malaysian Ministry of Education for her PhD study. She has taught classes in statistical process control and design of experiment at the University of Strathclyde. She is also a member of the American Society for Quality since 2012. Her current research interests are centered in the field of statistical process control, quality, operation management, quality engineering, engineering management and continuous improvement. For instructions on how to order reprints of this article, please visit our website: www.emeraldgrouppublishing.com/licensing/reprints.htm Or contact us for further details: permissions@emeraldinsight.com 691 A systematic review of Lean Six Sigma DownloadedbyHERIOTWATTUNIVERSITYAt15:4431May2015(PT)