The PhD literature review: its structure and contribution Steven Boyne ABSTRACT The paper examines the PhD literature review and makes recommendations for how to produce a literature review which assists in the generation of original, and defensible, research questions. Firstly, the contributions of the literature review as both a process and a product are examined. Guidance is then provided regarding the scope and structure of the literature review. The paper goes on to consider the specific requirements of PhD level study vis-a-vis lower-level academic endeavour. The requirements for depth, rigour and originality are highlighted using Bloom’s Taxonomy of Educational Learning Objectives and Anderson and Krathwohl’s revised taxonomy. Critical Thinking is proposed as a structured approach to enabling the generation of original research questions and for enhancing the defensibility of the choice of research these research questions. The author’s own research is used to illustrate how the overall conceptual framework can be disaggregated and each discrete section critically justified. Acknowledgements To Professor Roger Vaughan (Bournemouth University, School of Services Management) for providing the inspiration for this paper through his 2008 workshop on critical evaluation in the PhD study process. INTRODUCTION Every PhD candidate is faced with the prospect of undertaking and writing up the literature review. This paper aims to examine the specific contributions of the literature review to the overall research and also describes several methods for the design and execution of the literature review. To achieve these aims, the paper:   discusses the role of the literature review as both product and process; describes several practical issues related to designing and doing the  literature review;  and considers the need for depth and rigour in the literature review process; in the context of the requirement for the PhD study to make an original contribution to knowledge, the paper proposes Critical Thinking as a structured approach to enable this. The paper concludes by examining the conceptual framework for the author‟s own PhD research and highlighting the way in which the overall thesis is disaggregated and each discrete section is critically justified. The author recommends that candidates examine the application of Critical Thinking approaches to enhance the originality and, in particular, the defensibility of their work. THE LITERATURE REVIEW Broadly defined, the literature review is a systematic (different systems are described below) examination of the relevant research which has hitherto been conducted in the student‟s particular field of study. Hart (1998: 13) defines it as:  the selection of available documents (both published and unpublished) on the topic, which contain information, ideas, data and evidence;  [being] written from a particular standpoint to fulfil certain aims or express certain views on the nature of the topic and how it is to be investigated; and  the effective evaluation of these documents in relation to the research being proposed. Hart (p. 13) also writes that the literature review is “integral to the success of academic research” and contributes the “major benefit” of “ensuring the researchability” of the topic “before the ‘proper’ research commences”. Carnwell and Daly (2001: 57) rightly point out, however, the inherent conflict between Hart‟s statement and the role of the literature review in more relativistic research approaches, in particular the grounded theory approach, where researchers deliberately avoid having their observations and subsequent „grounded‟ theorising being contaminated by existing and previously published theories. Hart (1998: 13) hints at the dual nature of the literature review by describing it in: (i) tangible terms (the selection of available documents; [being] written from a particular standpoint); and (ii) more intangible terms (the effective evaluation of these documents) This reflects the author‟s own opinion that the literature review can be conceptualised as embodying two main dimensions: the processual and product dimensions. The literature review as process and product As a process the literature review assists the researcher in developing their knowledge of the subject matter. The process helps to clarify: (i) what research is actually required, that is, it helps the researcher formulate their broad aims and specific objectives; and (ii) practical ways to undertake the research (e.g. how previous similar work has been undertaken). The process of the literature review is an ongoing exercise and begins immediately that the researcher decides to do the research and continues to the last stages of the research when findings are theoretically integrated with the existing (and emerging) literature to develop conclusions and recommendations for further research. The product of this process is the 'literature review' chapter/s of the thesis; the literature review informs the reader of: (i) the background to the research; (ii) the rationale for the research; (iii) previous work that has been undertaken in this area (what has been found and how these findings have been achieved); and A further important function of the literature review is in periodically articulating the linkages between the existing literature and the research questions being addressed in the doctoral work. This assists the reader to keep track of how the arguments being raised in the literature review relate to the aims and objectives of the candidate‟s research. From an assessor‟s perspective, periodic articulation of the linkages between the existing literature and the aims and objectives of the current research provide an indication that the candidate is consistently addressing relevant topics and that the argument/s underpinning their aims and objectives are being generated from existing knowledge. It is the author‟s experience that, prior to engaging in their research dissertations/theses, many undergraduate and some masters students regard the literature review solely in terms of its product characteristics. That is, they marginalise the importance of the processual dimension. Hart (1998) goes on to expand his description of the literature review (p. 27) to include 11 separate purposes which the literature review should fulfil. These are illustrated in Figure 1. In contrast to the initial perspective of many students, therefore, we can see that when examining the literature review from an advanced perspective, all of its characteristics relate to its processual characteristics. Figure 1 Hart’s 11 purposes of the literature review 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. distinguishing what has been done from what needs to be done discovering important variables relevant to the topic synthesizing and gaining a new perspective identifying relationships between ideas and practice establishing the context of the topic or problem rationalizing the significance of the problem enhancing and acquiring the subject vocabulary understanding the structure of the subject relating ideas and theory to applications identifying the main methodologies and research techniques that have been used placing the research in a historical context to show familiarity with state-of-theart developments Source: (Hart 1998: 27) Designing and executing the literature review General points Carnwell and Daly (2001: 58) describe the following five „important‟ steps in planning and executing the literature review: 1. Defining the scope of the review 2. Identifying the sources of relevant information 3. Reviewing the literature 4. Writing the review 5. Applying the literature to the proposed study. In the author‟s experience, however, these steps do not occur concurrently, but are, to some extent at least, simultaneously undertaken. For example, defining the scope of the review is something that continues over time. That is, the broad scope is firstly outlined (this may have been done by the supervisory team or by the school or department research committee); the student then begins to search for relevant literature within this broad framework. As the student reviews the content of the literature new relationships and meanings become apparent; new research questions begin to form and alternative or additional themes and avenues for enquiry are developed. Some of these new directions may prove fruitful and relevant while others are rejected and discontinued. Rejection of a new direction may be on the grounds that: (i) the research focus would move too far away from the original theme; (ii) an significant change in approach or method would be required (perhaps beyond the student‟s experience or their learning objectives); or (iii) it is discovered that within the student‟s particular thematic area these questions have already been adequately addressed. This example demonstrates how steps one, two, and three of Carnwell and Daly‟s planning and execution framework can, in practice, be integrated. Furthermore, this integrative framework can quite easily be extended to include steps four and five. Specifically, many students will begin the writing process and also begin the continuous process of research question formulation, revision, reformulation etc. as the literature review progresses. Scope, sources and inclusion criteria Broad considerations related to the scope of the literature to be reviewed relate to the choices between a focus on empirical and theoretical papers and the desired type of source (peer-reviewed journals, technical/industry/applied books and reports, academic monographs, conference papers, project reports etc.). In the case of the empirical versus theoretical orientations, the student‟s choice may be guided by the nature of what‟s available, for example, there may be little in the way of developed theory in a particular area; conversely, there may a lot of theory and little empirical work. There may, of course, exist a plethora of theory and empirical works and the job of the student might then be to narrow the scope based on informed and justified criteria. Considerations regarding the type of source are guided by what‟s expected of PhD candidates in each particular field and – of course – where the relevant information is to be found. This author‟s work focuses on a specific aspect of organisational psychology and as a consequence there are many papers published in the applied psychology journals – but many of the theories used therein have been developed and expounded in published monographs. Similarly, this author‟s applied context is hospitality and catering – accordingly, relevant work can be found in hospitality-specific journals but once again, much of the theory underpinning hospitality studies has been developed in published monographs. Some students may be engaged in work with strong policy-relevance examples might include: town planning; rural development; resource allocation; transport geography; food safety and so on. In such areas students may find that a great deal of state-of-the-art applied and empirical work is being reported in commissioned reports (commissioners being government departments, local authorities, the European Commission and non-government bodies such as the Forestry Commission, Natural England or Scottish Natural Heritage). Specific inclusion (and exclusion) criteria are particular to each study although there may be broad disciplinary guidelines in this regard. Criteria for inclusion and exclusion of literature are often required in cases where there is a proliferation of (potentially) relevant material. Typical criteria which may be employed to guide the inclusion/exclusion of material include:    geographical, linguistic or chronological contexts scholarly status of information source (peer / non-peer reviewed) ontological, epistemological and methodological orientations The most simple and straightforward inclusion/exclusion criterion is probably „is it relevant to my aims and objectives or method?‟ – of course, since the precise nature of the aims, objectives and methods may very well be contingent on the findings from the literature review this may not be the most practical inclusion/exclusion criterion – at least during the earlier stages of the research. Some of these decisions discussed above may be contingent on candidate‟s choice of structure for the literature review – typical structures are discussed in the following section. Approach and structure of the literature review Figure 2 is based upon the University of New South Wales „general‟ guidelines for postgraduate students and describes four alternative approaches to structuring the literature review. Figure 2 Alternative structures for the literature review Chronological organisation The discussion of the research /articles is ordered according to an historical or developmental context. The 'Classic' studies organisation A discussion or outline of the major writings regarded as significant in your area of study. (Remember that in nearly all research there are 'benchmark' studies or articles that should be acknowledged). Topical or thematic organisation The research is divided into sections representing the categories or conceptual subjects for your topic. The discussion is organised into these categories or subjects. Inverted pyramid organisation The literature review begins with a discussion of the related literature from a broad perspective. It then deals with more and more specific or localised studies which focus increasingly on the specific question at hand. Source: (Ferfolja and Burnett 2009) An alternative classification of alternative literature review structures is provided by Carnwell and Daly (2001: 60-61) – this is summarised in Figure 3. Figure 3 Carnwell and Daly’s literature review structures Theoretical and methodological literature underpinning the study     Absence of empirical literature More exploratory approach may be required Critically evaluate existing theories and develop methods to conduct new study Integrate methodological insights from related research areas Theoretical and then the empirical literature in discrete sections     Theoretical and empirical works are available Review in two sections: theoretical and empirical domains Empirical section to include critical appraisal of methods previously employed Ensure internal consistency of theoretical and empirical arguments Dividing the literature into content themes    Helps address the issues of internal consistency of theoretical and empirical arguments Literature divided into distinct themes and theoretical and empirical domains within each theme examined Thematic approach can provide a robust and clear structure for the written review Examining the literature chronologically   Useful where subject matter has evolved over long periods of time (e.g. several decades) Also provides a clear structure for the written review Source: Carnwell and Daly (2001: 60-61) Carnwell and Daly (p. 62) go on to highlight the role of the conclusions which follow from the literature review and provide the following recommendations:   the findings from the literature review are summarised and integrated  shortcomings or merits of previous approaches/methods  this integration should articulate the gaps in knowledge and the the conclusions provide the theoretical underpinning for the new study this theoretical underpinning can now be used to justify the conceptual framework for the new study WORKING AT THE PHD LEVEL The function and form of the literature review can vary according to the educational level at which the work is taking place. Hart (1998) has summarised the main function and form differences thus: Undergraduate: Essentially descriptive. Topic focussed. Indicative of current sources on topic. Analysis of topic in terms of justification. Masters: Analytic and summative. Demonstration of knowledge of theoretical issues relevant to topic. PhD: Analytical synthesis covering all known literature on the topic. High level of conceptual linking within and across theories. evaluation of previous work. Summative and formative Depth and breadth of discussion on relevant philosophical traditions and ways they relate to PhD focus. (Hart 1998: 15) The transition from descriptive to analytical to evaluative which can be seen in Hart‟s description above is reflected in Bloom‟s (1956) taxonomy of educational learning objectives. Bloom identified three domains of learning: the cognitive, affective and psycho-motor domains. Within each domain Bloom proposed a series of levels each of which is based on the successful fulfilment of the previous level/s. The focus here is on the cognitive domain because it deals with sequential and progressive contextualisation of material (Atherton 2005) – a key aspect of undertaking a PhD level literature review. Figure 4 illustrates Bloom‟s six levels of educational learning objectives. Figure 4 Bloom’s taxonomy of cognitive domain learning objectives Source: after (Bloom 1956: 18) Vaughan (2008) has related Bloom‟s six levels of educational learning objectives to the PhD study context and presented these as follows: Level 1 – knowledge: restates previously learned material by recalling facts, terms, basic concepts and answers Level 2 – comprehension: demonstrates understanding of facts and ideas by organising, comparing, translating, interpreting, giving descriptions and stating main aims Level 3 – application: solves problems by applying acquired knowledge, facts, techniques and rules in a different way Level 4 – analysis: examines and breaks information into parts by identifying motives or causes; making inferences and finding evidence to support generalisations Level 5 – synthesis: compiles information together in a different way by combining elements in a new pattern or proposing alternative solutions Level 6 – evaluation: presents and defends opinions by making judgements about information, validity of ideas or quality of work based on a set of criteria But what is the ultimate objective, for the PhD candidate, of all this understanding, analysis, synthesis and evaluation? Andrew Broad (a computer scientist) provides a (very useful) list of „Nasty PhD Viva Questions‟ (Broad 2009) - his third question is What have you done that merits a PhD? One of the fundamental criteria for a PhD study is that it forms an original contribution to knowledge or understanding in the candidate‟s chosen field of study. If we consider Bloom‟s taxonomy in the light of the requirement to produce an original contribution, we can see how the taxonomy provides a structured model for examining, analysing, creating connections and integrating theory and practice towards revealing knowledge gaps and pertinent research questions. Another hierarchical conceptualisation of learning objectives which places the identification of knowledge gaps - and the subsequent filling of these gaps with „original‟ research questions - is that of Anderson and Krathwohl (2001). Those authors revised Bloom‟s taxonomy, replacing nouns with verbs and also to introducing a new „top‟ category describing the creation of new knowledge. Anderson and Krathwohl‟s taxonomy is illustrated in Figure 5. Figure 5 Anderson and Krathwohl’s taxnonomy, after Bloom Source: Anderson and Krathwohl (2001) cited in Atherton (2005) This „new‟ creative domain encapsulates to requirement for an „original contribution‟ insofar as the PhD candidate must (a) be creative in developing their original contribution and (b) the original contribution must also be defensible and justified (i.e. based upon the pre-requisite lower-level learning objectives). We have seen how Bloom‟s taxonomy of educational learning objectives provides a structured approach to understanding the hierarchical development from lower-level (undergraduate) study requirements to higher-level (masters and PhD) requirements. This paper has described how, ultimately, the PhD candidate is required to make an original contribution through their doctoral work; this „original contribution‟ dimension can be equated with the „creative‟ domain at the top of Anderson and Krathwohl‟s hierarchy of learning objectives. This paper goes on to suggest Critical Thinking (CT) as a useful approach for providing the foundations for creativity: that is, it is argued that CT can facilitate a justified articulation of knowledge gaps thus creating the „conceptual space‟ required for the creation of new theories and research questions. AN INTRODUCTION TO CRITICAL THINKING Critical Thinking has been defined in various ways in the social science and pedagogological literature. Two definitions with particular relevance to the present context are provided below: [Critical thinking is] …the examination and test of propositions of any kind which are offered for acceptance, in order to find out whether they correspond to reality or not. (Sumner 1940: 632) It presupposes assent to rigorous standards of excellence and mindful command of their use. It entails effective communication and problemsolving abilities… (Foundation for Critical Thinking 2008 ) King (1994, cited in Cho et al. 2002: 26) argued that those who are able to think critically have the capacity to:   analyse situations;  look for and make connections among aspects of a situation; and  search for complexity and ambiguity; speculate, search for evidence, and seek links between a particular situation and their prior knowledge and experience. King‟s description of the attributes which CT can bring to bear upon a piece of academic work appear to be highly relevant for the PhD candidate who is seeking a set of arguments and justifications for a original thesis. Other benefits which CT can bring for the PhD candidate are alluded to in Paul (1992), where he defines CT as: the art of thinking about your thinking while you are thinking, in order to make your thinking better, more clear, more accurate, or more defensible (Paul 1992: 7) Reflecting on Paul‟s comments above, we can see how clarity, accuracy and defensibility are all key criteria for a successful PhD thesis. So, CT can provide a structured way to develop insights and arguments which lead to, and underpin, original, „creative‟ approaches to addressing information needs. Furthermore, Paul‟s definition of CT suggests that as an approach it may assist the PhD candidate by enhancing the defensibility of their thesis. How, then, should CT be employed in the PhD process? clarity, accuracy and How to use CT in the PhD research process For Glaser (1941: 5-6), using CT required: 1. an attitude of being disposed to consider in a thoughtful way the problems and subjects that come within the range of one's experiences; 2. knowledge of the methods of logical inquiry and reasoning; and 3. some skill in applying those methods. With respect to point (2), the methods of logical inquiry and reasoning cover a meant various dimensions, including:   examining propositions in the light of the supporting evidence;  these;  recognising unstated assumptions and values;  discrimination;  recognising problems and developing workable means of addressing gathering and marshalling pertinent information; understanding and using language with accuracy, clarity  interpreting data, appraising evidence and evaluating arguments;  between propositions;  critically examining or testing these conclusions and generalisations;   and recognising the existence (or non-existence) of logical relationships developing justified conclusions and generalisations; reconstructing one‟s own beliefs on the basis of wider experience; and delivering accurate assessments of everyday phenomena. It is not possible for this short paper to provide a comprehensive account of how CT can be used in the PhD literature review (and wider research) process. Suffice to say, if a candidate follows Glaser‟s definition and methods, desirable results should be forthcoming. The aim in this section of the paper has been to introduce CT as a method for critical appraisal which can assist the candidate critically examine the literature (and their own beliefs) towards generating original/creative research questions and methods for satisfying the information needs of these questions. Furthermore, following Paul‟s (1992: 7) reflections on CT, it is recommended as an approach which can enhance the clarity, accuracy and defensibility of the PhD work. The remainder of this paper very briefly outlines the author‟s research and uses this as an example of how the CT approach to the literature review can assist in revealing knowledge gaps (which can then pave the way for the creation of novel research questions). EXEMPLIFYING CRITICAL THINKING IN THE PHD LITERATURE REVIEW In the following example, one of the key reflections of the use if CT in the research process is not readily highlighted since the manifestation of it is specifically NOT present in the research design. That‟s a rather long-winded way of pointing out that, to a large extent, the principles of CT as described by Glaser (1941; see above) have been applied in the critically-justified rejection of alternative theories and methods. While the details of, and arguments for, the selection of certain theories and methods (and the rejection of others) will be detailed in the relevant section of this candidate‟s thesis, there is not sufficient space to do that here. Figure 7, however, is intended to give a flavour of how the various dimensions of the overall work have been dealt with as discrete components which each have their own specific set of arguments and justifications. Context and aims for the work The author‟s PhD research uses structural equation modelling (SEM) to examine the role of the motivational dimension of transformational leadership (known as the Inspirational Motivation (IM) dimension) in contributing to catering service staff members‟ work meaning and work motivation. The model also seeks to establish and evaluate the influence of any observed enhancement of service staff work meaning and motivation on catering service quality. With regard to leadership and human resource management issues in the catering context, the work provides recommendations regarding: (i) the selection of managers/leaders; (ii) staff management (leadership) practices; and (iii) service staff training and selection. The work also seeks to improve our understanding of the nature and contribution of transformational leadership to service quality in the catering, hospitality and more general service contexts. The aims of the research are, therefore:   to evaluate the influence of transformational leadership on catering service staff work meanings and motivation; and to assess any subsequent influence of enhanced service staff work meaning and motivation on catering service quality. The overarching rationale for the work is captured succinctly in Hartline and Ferrell‟s (1996) conclusions from their review of the literature relating to the management of customer-contact service employees. They write that: The findings from previous research lead to two major conclusions: (1) managers can influence customer-contact employees' responses so as to enhance service quality and (2) the responses of customercontact employees heavily influence customers' perceptions of service quality and the service encounter (Hartline and Ferrell 1996: 52-53) Figure 6 illustrates the specific relationships which will be examined in the research. Illustrated are the Inspirational Motivation dimension of transformational leadership and the relationships between this dimension and (i) the discrete Motivation and Meaning dimension and (ii) the service quality dimension. The theoretical framework which has been developed also suggests that a number of other dimension will co-exist alongside the Inspirational Motivation dimension to influence Motivation and Meaning (and subsequently/indirectly) Service Quality. These dimensions are also illustrated on the left hand side of Figure 6. Figure 6 The relationships to be examined in the PhD Inspirational Motivation (Dimension of transformational leadership) Organisational commitment Motivation Meaning of Work/ Work values Service quality Career Identity / Primacy of Work / Career resilience Meaning Empowerment / Autonomy Source: author Developing the research design The specific foci, approaches and methods which have been selected for the work have been arrived at following a structured approach to the literature review and the application of, as Glaser (1941: 5) puts it, “knowledge of the methods of logical inquiry and reasoning”. The overarching field of study is organisational psychology and, in particular, leadership studies; the applied focus is catering in the hospitality sector. Figure 7 summarises how these specific themes and the selected ways of measuring them were chosen. Rows one and two provide the justification for the theoretical and (specific) applied contexts while rows three to five describe the rationale for the choices of the specific variables which will be observed. This type of critical and justified selection process reflects what Hart (1998: 13) described the role of the literature review in “the progressive narrowing of the topic” (emphasis in original). This narrowing was achieved by identifying knowledge gaps and developing research questions and study methods to address these whilst continuously applying the principles of CT. Figure 7 Rationale and justification for the research design Design aspect Rationale and justification Theoretical framework Leadership and hospitality are both relational phenomena Applied context Specific hospitality focus to enhance measurement validity Inspirational motivation addresses typical hospitality sector customer-contact (front-of-house) employment characteristics Catering service typified by an extended and relatively intimate service encounter (host-guest interaction) Leadership outcomes (measurements) Work meaning, motivation and service quality correspond with typical individual- and organisational-level leadership outcomes reported in the literature Service quality Correlation of service staff and customer assessments of service outcomes quality have been successfully demonstrated (measurements) Non-leadership variables Inspirational motivation is not the only source of work meanings and motivation Non-leadership variables drawn from a review of organisational behaviour literature relevant to work meanings and motivation Source: author CONCLUSIONS This short paper has examined the different roles which the literature review performs within the broader PhD research process and has also described a variety of approaches to planning, organising and executing the literature review. Bloom‟s Taxonomy of Educational Learning Objectives has been used to exemplify the different levels of learning objectives and how PhD-level research requires an element of creativity. The concept of Critical Thinking (CT) has been proposed as a structured method to reveal knowledge gaps and assist in generating „creative‟ solutions in the form of original research questions. The structured CT approach should also enhance the defensibility of the research by helping the candidate to justify the arguments which underpin the research questions and chosen methods. Fundamentally, the paper has described how structured and considered approaches to undertaking the literature review relate to:  Standards of: 1. comprehension of literature content; 2. synthesis and analysis of literature content; and 3. application of knowledge  The requirements to: 1. narrow the focus of the study; 2. critically justify the chosen focus; 3. synthesise complex arguments; 4. develop new insights; 5. create new research designs; 6. communicate effectively by utilising structured arguments; and 7. maintain an excellent standard of work throughout these endeavours. List of references Anderson, L. W., and Krathwohl, D. R. (Eds.). 2001. A Taxonomy for Learning, Teaching, and Assessing: A Revision of Bloom's Taxonomy of Educational Objectives. New York: Longman. Atherton, J. S., 2005. Learning and Teaching: Bloom's taxonomy. Available from: http://www.learningandteaching.info/learning/bloomtax.htm [Accessed: 11/04]. Bloom, B. S. (Ed.). 1956. Taxonomy of Educational Objectives, the classification of educational goals – Handbook I: Cognitive Domain. New York: McKay. Broad, A., 2008. Nasty PhD Viva Questions. Available from: http://www.geocities.com/andrewbroad/cs/cs710/viva.html [Accessed: 02/04]. Carnwell, R., and Daly, W., 2001. Strategies for the construction of a critical review of the literature. Nurse Education in Practice, 1 (2), 57-63. Cho, W., Schmelzer, C. D., and Mcmahon, P. S., 2002. Preparing Hospitality Managers for the 21st Century: The Merging of Just-in-Time Education, Criticalthinking, and Collaborative Learning. Journal of Hospitality & Tourism Research, 26 (1), 23-37. Ferfolja, T., and Burnett, L., 2009. Getting Started on Your Literature Review: A General Guide for Postgraduate Research Students. Available from: http://www.lc.unsw.edu.au/onlib/litrev2.html [Accessed: 07/04]. Glaser, E., 1941. An experiment in the development of critical thinking. New York: J. J. Little and Ives Company. Hart, C., 1998. Doing a literature review: releasing the social science research imagination. London: Sage Publications. Hartline, M. D., and Ferrell, O. C., 1996. The Management of Customer-Contact Service Employees: An Empirical Investigation. Journal of Marketing, 60 (4), 52-70. Paul, R., 1992. Critical thinking: What every person needs to survive in a rapidly changing world. 2nd ed. Santa Rosa, CA: Foundation for Critical Thinking. Sumner, W. G., 1940. Folkways: A Study of the Sociological Importance of Usages, Manners, Customs, Mores, and Morals. New York: Ginn and Co. Thinking, F. F. C., 2008. Our Concept of Critical Thinking. Available from: http://www.criticalthinking.org/aboutCT/ourConceptCT.cfm [Accessed: 02/04/2009]. Vaughan, D. R. 2008. School of Services Management PhD Workshop: Bournemouth University.