Evidential verbs in the genre of medical posters

Table Of Contents

• Cover
• Title
• Copyright
• About the author
• About the book
• This eBook can be cited
• Table of contents
• List of tables
• List of figures
• Acknowledgements
• Chapter 1 Introduction
• 1.1. Overview
• 1.2. Research scope
• 1.3. Volume synopsis
• Chapter 2 Setting the theoretical framework
• 2.1. Academic discourse, academic communities and academic disciplines
• 2.2. Genre analysis
• 2.3. Medical discourse and medical genres
• 2.3.1. The genre of medical posters
• 2.4. Evidentiality key concepts
• 2.4.1. Introduction
• 2.4.2. Evidentiality: definition and literature review
• 2.4.3. Evidentiality and epistemic modality: setting the boundaries?
• 2.4.4. Evidentiality in this volume
• 2.4.5. Evidentiality and construction grammar
• 2.4.6. Issues of conventionalization in evidentiality
• 2.4.7. Patterns of responsibility attribution
• 2.4.8. Evidentiality, factuality and the factual claim
• 2.4.9. Summary
• 2.5. Corpus Linguistics
• 2.6. Conclusion
• Chapter 3 Medical posters discourse
• 3.1. The medical poster
• 3.1.1. Poster types
• 3.1.2. Summary
• 3.2. Medical poster sessions
• 3.2.1. The 2011 NCRI National Cancer Conference
• 3.2.2. The Meningitis and Septicaemia in Children and Adult 2011 Conference
• 3.3. Conclusion
• Chapter 4 Methodological approach(es)
• 4.1. Introduction
• 4.2. Corpus design and corpus-building
• 4.3. The sample corpus
• 4.3.1. Introduction
• 4.3.2. Building the sample corpus: why and how
• 4.4. Main corpus selection
• 4.5. Using CL Tools: Wordsmith Tools and WMatrix
• 4.5.1. WordSmith Tools
• 4.5.2. Concordance analysis
• 4.5.3. WMatrix
• 4.5.4. Statistical significance metric
• 4.6. Source and mode of knowledge. Text-driven and text-based identification
• 4.7. Source of knowledge: None. Mode of knowledge: Belief
• 4.8. Source of knowledge: Hypothesis. Mode of knowledge: Deduction
• 4.9. Source of knowledge: Language. Mode of knowledge: Hearsay
• 4.10. Source of knowledge: Evidence. Mode of knowledge: Induction or inference
• 4.10.1. Source of knowledge: Evidence. Mode of knowledge: Induction – Commonly-shared knowledge
• 4.10.2. Source of knowledge: Evidence. Mode of knowledge: Induction – Inference based on perception
• 4.10.3. Source of knowledge: Evidence. Mode of knowledge: Induction – Inference based on reasoning/perceptual reasoning
• 4.11. Sources and modes of knowledge: do potential evidential markers function as evidentials in context?
• 4.12. Sources and modes of knowledge. Summary
• 4.13. Conclusion
• Chapter 5 Identifying evidential markers in a sample corpus
• 5.1. Introduction
• 5.2. The sample corpus: methodological issues and manual analysis results
• 5.3. Belief evidentials
• 5.4. Deduction evidentials
• 5.5. Hearsay evidentials
• 5.5.1. According to
• 5.5.2. Author/Institution, year or (footnote to ref. list)
• 5.5.3. Hearsay evidentials as verb phrases
• 5.5.4. Indicate
• 5.5.5. Find
• 5.5.6. Record
• 5.5.7. Reported, represented and stated
• 5.6. Induction evidentials
• 5.6.1. Induction evidentials: commonly-shared knowledge
• 5.6.2. Induction evidentials: based on perception
• 5.6.2.1. Metadiscursive induction evidentials based on perception
• 5.6.2.2. Metaphorical induction evidentials based on perception
• 5.6.2.3. Appear* and Seem*
• 5.6.2.4. Demonstrat*
• 5.6.2.5. Illustrate
• 5.6.2.6. Indicat*
• 5.6.2.7. Reveal*
• 5.6.2.8. Seen
• 5.6.2.9. Show*
• 5.6.2.10. Clear
• 5.6.3. Induction evidential: based on reasoning
• 5.6.3.1. Confirms
• 5.6.3.2. Demonstrated
• 5.6.3.3. Find
• 5.6.3.4. Suggest
• 5.7. Implications for the main study
• 5.8. Conclusions
• Chapter 6 Expanding the list of evidential verbs
• 6.1. Introduction
• 6.2. Evidential marker identification in the main corpus
• 6.3. Enlarged list of potential evidential expressions
• 6.4. Blurred cases: verbs that can convey two or more or different evidential meanings
• 6.5. Recap
• Chapter 7 Distribution, type of verbal evidentiality in the main corpus
• 7.1. Quantitative analysis
• 7.2. Qualitative analysis
• 7.2.1. Poster Introduction Section
• 7.2.2. Poster Methods Section
• 7.2.3. Poster Results Section
• 7.2.4. Poster Conclusions Section
• 7.3. Conclusion
• Chapter 8 Patterns of source attributions and forms of factual claims
• 8.1. Responsibility attribution across IMRC: Quantitative analysis
• 8.1.1. Responsibility in belief evidentiality
• 8.1.2. Responsibility in deduction evidentiality
• 8.1.3. Responsibility in hearsay evidentiality
• 8.1.4. Responsibility in commonly-shared evidentiality
• 8.1.5. Responsibility in perception evidentiality
• 8.1.6. Responsibility in reasoning evidentiality
• 8.1.7. Summary
• 8.2. Responsibility attribution across IMRC: Qualitative analysis
• 8.2.1. Human responsibility: self-mention
• 8.2.2. Human responsibility: scholarly quotation
• 8.2.3. Abstract responsibility: unquoted literature
• 8.2.4. Abstract responsibility: quoted literature
• 8.2.5. Abstract responsibility: research data
• 8.2.6. Abstract responsibility: research processes
• 8.2.7. Unspecified responsibility
• 8.2.8. Summary
• 8.3. The factual claim: quantitative analysis
• 8.3.1. Summary
• 8.4. Evidential patterns of responsibility attribution and factual claims: Discussion and conclusions
• Chapter 9 Rhetorical function of evidential categories
• 9.1. Rhetorical function of belief evidentiality
• 9.2. Rhetorical function of deduction evidentiality
• 9.3. Rhetorical function of hearsay evidentiality
• 9.4. Rhetorical function of induction evidentiality based on perception
• 9.5. Rhetorical function of induction evidentiality based on reasoning
• 9.6. Rhetorical function of induction evidentiality based on commonly-shared knowledge
• 9.7. Summary and conclusions
• Chapter 10 Focusing on specific verbs
• 10.1. Suggest
• 10.1.1. Quantitative analysis
• 10.1.2. Qualitative analysis
• 10.1.2.1. Suggest and unquoted literature asserting a factual claim
• 10.1.2.2. Suggest and research data expressing a factual claim
• 10.1.2.3. Suggest and research processes expressing a factual claim
• 10.1.2.4. Suggest and unspecified responsibility attribution: the case of anaphorical THIS
• 10.2. Show
• 10.2.1. Quantitative analysis
• 10.2.2. Qualitative analysis
• 10.2.2.1. Evidential sub-categories of show
• 10.2.2.2. Show as a perception evidential
• 10.2.2.3. Show as a perception evidential: research data asserting a factual claim
• 10.2.2.4. Show as a perception evidential: research processes asserting the factual claim
• 10.2.2.5. Show as a reasoning evidential
• 10.2.2.6. Show as a reasoning evidential: self-mention asserting a factual claim
• 10.2.2.7. Show as a reasoning evidential: unquoted literature asserting a factual claim
• 10.2.2.8. Show as a reasoning evidential: research data asserting a factual claim
• 10.2.2.9. Show as a reasoning evidential: research processes asserting a factual claim
• 10.2.2.10. Show as a reasoning evidential: unspecified responsibility
• 10.3. Suggest and Show: Conclusions
• Chapter 11 Concluding remarks
• 11.1. Evidential verbs in medical posters
• 11.1.1. What evidential verbal markers?
• 11.1.2. Verbal markers distribution across medical posters
• 11.1.3. Patterns of responsibility across medical posters
• 11.1.3.1. Responsibility
• 11.1.3.2. Factual claim
• 11.1.3.3. Patterns
• 11.1.4. Evidential verbal functions
• 11.2. Theoretical contribution
• 11.3. Methodological contribution
• 11.4. Empirical contribution
• 11.4.1. Quantitative results
• 11.4.2. Qualitative results
• 11.4.3. Case studies
• 11.5. Pedagogical contribution
• 11.6. Limitations and future research
• Appendix I – Background survey
• Appendix II – Semi-structured interview to poster presenters
• Appendix III – Statistical analysis
• References
• Series Index

←12 | 13→

List of tables

Table 2.1. Chafe’s (1986) notion of evidentiality.

Table 2.2. Summary of Anderson’s (1986: 273–312) definition of evidentiality.

Table 4.1. Breakdown of poster sub-corpora.

Table 4.2. Breakdown of poster sub-corpora over time.

Table 4.3 Breakdown of pilot corpus.

Table 4.4. Classification of evidentiality according to Chafe (1986).

Table 4.5. Evidentiality. Source and mode of knowledge (adapted from Chafe (1986); Anderson (1986)).

Table 5.1. List of evidentials.

Table 5.2. List of evidential markers found in the sample corpus following Chafe’s framework.

Table 5.3. Agency and complement patterns collocating with appear*.

Table 5.4. Subjects and complements collocating with demonstrat*.

Table 5.5. Agency and complement patterns collocating with indicat*.

Table 5.6. Agency and complement patterns collocating with reveal*.

Table 6.1. List of sample corpus evidentials and their SEMTAGs.

Table 6.2. List of SEMTAGs and corresponding potential evidentials.

Table 6.3. Enlarged list of evidentiality in the main corpus and frequencies.

Table 6.4. Evidential lexical markers and evidential categories in the main corpus.

Table 7.1. Evidentiality across IMRC.

Table 7.2. Frequency of evidential category.

Table 7.3. Evidential categories across IMRC.

←13 | 14→

Table 7.4. Verbal evidential distribution across IMRC.

Table 8.1. Distribution of responsibility across posters.

Table 8.2. Responsibility attribution in hearsay evidentiality.

Table 8.3. Responsibility attribution in perception evidentiality.

Table 8.4. Responsibility attribution in reasoning evidentiality.

Table 8.5. Evidential pattern and that-clauses.

Table 8.6. Evidential patterns and infinitive clauses.

Table 8.7. Evidential patterns and nominalization.

Table 9.1. Breakdown of hearsay evidentiality across IMRC.

Table 9.2. Breakdown of induction evidentiality based on perception across IMRC.

Table 9.3. Breakdown of induction evidentiality based on reasoning across IMRC.

Table 10.1. Distribution of responsibility attribution for suggest (hearsay) and factual claim.

Table 10.2. Distribution of responsibility attribution for suggest (induction) and factual claim.

Table 10.3. Show as a reasoning evidential: distribution of responsibility attribution and factual claim across IMRC.

Table 10.4. Past and perfect forms of show with responsibility and factual claim across IMRC.

←14 | 15→

List of figures

Figure 1.1. Poster session at the Neuroscience 2016 Convention in San Diego.

Figure 2.1. Move and step structure in RAs. Adapted from Swales (2004: 230–2).

Figure 2.2. Willet’s (1988) types of evidentiality.

Figure 2.3. Hart’s (2011: 758) semantic domains of evidentiality.

Figure 3.1. Horizontal poster sample.

Figure 3.2. Vertical poster sample.

Figure 3.3. Horizontal poster template following the IMRC pattern.

Figure 3.4. Vertical poster template following the IMRC pattern.

Figure 3.5. Horizontal poster with text and images aligned vertically.

Figure 3.6. Vertical poster with text and images aligned vertically.

Figure 3.7. Vertical poster with text and images aligned in a disrupted way.

Figure 3.8. Horizontal poster with text aligned vertically on the left, and images on the right.

Figure 3.9. Horizontal poster with text aligned vertically, and Conclusions found at the top right.

Figure 3.10. Vertical poster with text aligned vertically, and Conclusions found on the top right.

Figure 3.11. Horizontal poster with text only.

Figure 3.12. Visuals supporting the text.

Figure 3.13. Visuals introduced by the text

Figure 3.14. Visuals as text.

Figure 3.15. Hall 2 floor-plan: location of poster boards (left and right, margins) and exhibitor stands (centre).

Figure 3.16. Poster stand sample.

←15 | 16→

Figure 4.1. Example showing a concordance analysis of according to.

Figure 4.2. Patterns of according to.

Figure 4.3. Concordance list of state.

Figure 4.4. USAS. Semantic classification of state.

Figure 4.5. Example of an evidential based on perception.

Figure 5.1. Metadiscursive evidentials based on perception.

Figure 7.1. Evidentiality distribution at a glance.

Figure 7.2. Example of demonstrate as perception evidential.

Figure 8.1. Poster P510. Representation of the pattern data indicate.

Figure 8.2. Poster P031. Representation of the pattern our data/findings.

Figure 8.3. Visual excerpt from Poster P181. Representation of the pattern our data show.

Figure 8.4. Representation of the pattern research processes indicate.

Figure 8.5. Factual claim variation.

Figure 8.6. Factual claims distribution across IMRC.

Figure 8.7. Factual claim distribution across evidential categories.

Figure 10.1. Breakdown of responsibility attribution for suggest.

Figure 10.2. Research processes and suggest in the Results section of P064.

Figure 10.3. Breakdown of factual claims for show.

Figure 10.4. Breakdown of responsibility attribution for show.

Figure 10.5. Evidential categories of show across IMRC.

Figure 10.6. Example of show as a perception evidential (P140).

Figure 10.7. Panel A of Figure 2 of poster P195.

←16 | 17→

Acknowledgements

This volume is the result of a long research starting which has resulted in a never-ending work-in-progress.

Clearly, this would not have been possible without the help and contribution of some people I would like to thank.

First and foremost, thanks to Elena Semino and Greg Myers, for their invaluable help, comments, feedback, positive criticism and long Skype calls; for their insightful questions, suggestions: I will never ever forget their teaching and their sensitivity.

My special thanks go to Vittorio Tantucci and Paul Thompson who patiently read through the original work as a thesis and gave me interesting, provoking and intriguing feedbacks, which has been rewarding.

Also, thanks to my colleagues, Prof. Matteo Kalchschmidt, from the School of Engineering, University of Bergamo, Italy, Prof. Paolo Buonanno and Prof. Michela Cameletti from the Department of Economics, University of Bergamo, Italy, and special thanks to Dr Costas Gabrielatos, from Edge Hill University, UK, for patiently explaining the mysteries of statistics to me. Without their explanations, the statistics could never have been significant.

My thanks to Maurizio Gotti for being my mentor, for his technical and human support. I could have never reached this goal without his help.

To Michele Sala for discussions on evidentiality over lunch breaks, during Christmas, Easter and summer vacations, via Whatsapp, email, Messenger, phone calls or whatever, no matter where he was or what he was doing. Despite not knowing anything about evidentiality, he is now an expert. Thank you.

To Ferdinand de Haan for long and witty email conversations on evidentiality. Thank you for disentangling the doubts about suggest.

To De Castro at ISS and her colleagues at www.iss.com for explaining the joys and sorrows of writing a poster in the medical field.

To Il Pensiero Scientifico, for helping me disseminate the online survey.←17 | 18→

To Roulette Smith, Director at Humanized Technologies, San Francisco Bay Area, US, for helping me with the elaboration of the online survey, the interview and poster collection, and the long chats.

To all the medics, who prefer to remain anonymous, working in Academia for answering the survey and agreeing to be interviewed.

To David Svinarich, Vice President of Research, Ascension Southeast Michigan Director, Biomedical Research and SJP Research and Development, Ascension Providence Hospital, and Julie M. Zito (PhD), Professor of Pharmacy and Psychiatry, Pharmaceutical Health Services Research Dept., University of Maryland, Baltimore, for sending me their posters.

To the CROI Secretariat at https://www.croiconference.org/ for letting me download the corpus I needed for my investigation.

To Rebecca Lawrence (PhD), Managing Director, New Product Development at F1000, for helping me with the poster collection at www.F1000.com.

To Gerard Hearne, for his invaluable work – and friendship.

To Dr. Sylvia Jaworska, at the University of Reading (UK), a great friend, to her husband and Livy, who created an especially-made writing retreat for me at Reading, UK.

To my family, for their support, trying to understand what I am doing, nodding approvingly at my explanations and then asking for clarification. Thank you, for making this volume possible.

Two sections in Chapter 2 have been a further elaboration and extension on previous publications, for which I acknowledge the Editors:

←18 | 19→

Chapter 1 Introduction

1.1. Overview

The purpose of this volume is to provide information about and interpretations of the concept of evidentiality lexically realized with certain verbs and applied to the genre of medical posters. More specifically, I would like to discuss issues relating to how knowledge is conveyed through language and how evidence for such knowledge is linguistically transmitted in a set of specialised texts. This requires a more in-depth discussion about the concept of evidentiality than the one offered for general discourse. Aikhenvald (2007: 209) defines evidentiality as a linguistic category that indicates “how one knows what one is talking about”, that is, how knowledge is asserted by a source validating the information conveyed. We will see the extent to which this definition can be applied, in particular, to medical posters prepared to be presented at international scientific conferences. As we will see, posters are a very condensed genre whose main constraint is space limitation. Furthermore, medicine is an empirical science, which exploits inductive reasoning, in that generalization and theoretical abstraction derive from specific observations of certain phenomena. I will, therefore, seek to detect how the development of theories from observation is reproduced in the written language of posters. Specifically, I will look at the ways in which scientific claims are validated by issues of evidentiality in medical posters, where evidentiality is the semantic category that indicates the source of information validating a scientific claim (cf. Aikhenvald 2004).

The aim of academic medical posters is to present scientific ideas, projects and research in progress, in visual form, to be discussed at conferences in order to establish productive interaction with the audience. As such, posters are perceived as tools by means of which knowledge ←19 | 20→may be better grasped than oral presentations (Whimster 1989). Therefore, posters have a relevant role at scientific conferences.

Academic posters occupy an, as yet, largely unexplored territory across genres, and so very few investigations (Dubois 1985a, 1985b; MacIntosh-Murray 2007) have been carried out on posters from a linguistic angle, probably because the genre of posters is perceived by certain academic disciplines as a genre for junior members of the research community. In addition, the existing literature on posters seems to be descriptive rather than interpretative, and particularly targeting PhD students and junior researchers (see, for instance, Swales and Feak 2000). Nevertheless, posters are of theoretical interest to English for Specialised Purposes (ESP) for a number of reasons. For instance, they are an extremely compressed genre, which requires different types of discursive and rhetorical strategies; they have a strong relation between both visual and oral components, as they are written to stand alone, but also to be presented in just 10–15 minutes; they must compete for attention in crowded conferences, as can be seen in Figure 1, below:

←20 | 21→As claimed by Rowe and Ilic (2009b: 70; cf also Rowe 2017), posters are perceived by the scientific community as a “good medium for transferring knowledge and a valid form for academic publication”. Indeed, posters are a visual representation of an overall scientific message that is discussed at conferences and eventually published in academic journals. This latter point requires that students can competently use the most common linguistic strategies employed in posters to validate and justify knowledge transmission through issues of evidentiality. Such aspect can be relevant for ESP/EAP studies, particularly outside the UK, where English is used as a second language and where it can be difficult to perceive how the rhetorical purposes of the poster genre can have an impact on the use of evidentiality as recorded and classified by the medical science. This can allow students to learn the needed literacy required to create a poster and, in the future, offer new developments in EAP teaching.

In medicine the scientific poster plays a crucial role in the construction and transmission of knowledge, and this requires specific training for students in their future professional and academic lives in terms of linguistic preparation. This explains the reason why posters have been selected as a genre to be investigated

This study makes use of some of the possibilities offered by electronic corpora in conjunction with concordance tools, which allow quantitative analysis. In particular, two corpus tools have been used to detect all possible evidential lexical markers used across the corpus and analysed in linguistic co-text and collocational patterns (Sinclair 1991, 2004). This is accompanied by a qualitative interpretation of data, in order to conduct a complete examination of the way in which scientific communication is constructed in this genre. Indeed, thanks to this qualitative analysis I was able to detect the pragmatic function these evidential items have in contextual use, which then allowed me to see that evidentiality in medical discourse is intended in a slightly different way from general discourse. The quantitative and qualitative analyses are complementary, as the advantages of automatic data processing and consistency in data processing are accompanied by the analysis of the pragmatic functions of language in use, which are thus not de-contextualised. Furthermore, data interpretation has been ←21 | 22→cross-checked with information gathered by professional informants so as to avoid any biased construal of professional communication.

In the following sections of this chapter, the research scope and a brief summary of the chapters in this volume will be outlined.

1.2. Research scope

Evidentiality has a long history in the grammar of other languages, but in English much of the study of evidentiality starts with the seminal work by Chafe and Nichols (1986), from which developed two perspectives, a narrower one and a broader one. In the narrower definition, evidentiality expresses “the kind of evidence a person has for making factual claims” (Anderson 1986: 273), that is, whether information is heard, seen, inferred or told (Aikhenvald 2008), as in the sentence, for instance

I hear that Colin Firth won the Oscar

where I hear that indicates that the information Colin Firth won the Oscar has been heard somewhere.

In the broader definition, evidentiality, while expressing evidence for information conveyed, also provides a series of devices indicating the speaker’s attitude to that knowledge (Chafe 1986). For example, the use of such adverbs as allegedly, supposedly, undoubtedly, certainly etc. indicate the speaker’s attitude towards information, as in the following sentence:

He was undoubtedly precise in writing his reply

These two approaches to the same concept of evidentiality mean that the identification of evidentiality is not straightforward. Therefore, for the purposes of this volume, I will adopt a narrow definition of evidentiality. Indeed, as Aikhenvald (2004) explains, the representation of attitude may overlap with evidentiality, but that does not mean that evidentiality is also attitudinal. This approach, well explained by Dendale ←22 | 23→and Tasmowski (2001: 342), is confirmed by de Haan (1999, 2001a, 2001b).

A consideration of evidentiality requires a consideration of the sources of evidence. This has made scholars concentrate on issues of objectivity, subjectivity and intersubjectivity (Willet 1988; Langacker 1990; Nyuts 2001a; Whitt 2011). Since, in medical discourse, the purpose of the author is that of sharing information with a scientific audience, in medical posters the type of knowledge source is by default always intersubjective (cf. Nyuts 2015). For this reason, this volume will concentrate on the entity to which the poster author assigns responsibility for information conveyed in factual claims and asserted through evidential markers.

While previously studies on evidentiality have been conducted in English on general discourse (Aikhenval 2004, 2018; Björn and Stathi 2010; Marín-Arrese et al. 2013, 2017a), my analysis will try to analyze the role evidentiality has in medical discourse in order to understand what we can learn about evidentiality by focusing on this specific genre and field; more specifically, the purpose will be that of detecting specialised aspects and functions of evidentiality in the medical disciplinary context for pedagogical reasons within English for Academic and Specialized Purposes, with the aim of making a practical contribution to language in use in a seldom investigated field, and to show how researchers use the discipline’s linguistic resources to convey scientific knowledge.

The medical posters that will be analysed belong to the epidemiological field, for reasons explained in Chapter 4. For the purposes of this volume’ investigation, only written texts will be analysed, as the study of visual components would require a different approach which is beyond the scope of this volume. A narrower definition of evidentiality will be applied to my investigation, which is based on Anderson (1986) and refers to the kind of evidence a person has for making a factual claim providing some information, without taking into consideration the speaker’s/ writer’s attitude to that information. Evidentiality in English is realized with a series of lexical strategies, which, as indicated by Aikehnvald (2007: 209) can be “heterogeneous and versatile” since they may include, amongst others “closed classes of particles and modal verbs, and an open-ended array of verbs of opinion and ←23 | 24→belief”. In addition, if we consider that the syntactic behaviour of verbs is semantically determined (Dixon 2005), an analysis of the behaviour of the evidential verbs will better define the semantic value these verbs have across the as Introduction, Methods, Results and Discussion/ Conclusions in an academic medical context. Furthermore, as we will see on Chapter 5, medical discourse mainly realizes evidentiality in verbal forms. For this reason, in this volume I will concentrate on evidential verbs.

1.3. Volume synopsis

This volume consists of eleven chapters. Following this Introduction, which provides the background to this study and the study’s objectives, Chapter 2 explains the study’s theoretical background by reviewing the current literature on medical discourse and genres, and the genre of medical posters in particular. It also covers key points in evidentiality and sets the boundary between evidentiality and evaluation, as well as between evidentiality and modality. It thus positions the study beyond these theoretical frameworks, which contain a broader definition of evidentiality, one traditionally including attitudes towards sources of knowledge. In contrast, the chapter positions the volume within a theoretical framework that contains a narrower definition of evidentiality, without any interpretative evaluation of the factual claims it asserts. Furthermore, aspects related to sources of information and types of factual claims will also be taken into consideration. As the study is corpus-based and text-driven, an explanation of the core issues of corpus linguistics will be also given in this chapter.

Chapter 3 illustrates posters, describing their layout, showing their visual and verbal components and how these are strictly interlinked in order to create meaning. Furthermore, this chapter describes poster sessions at two different medical conferences.

In Chapter 4, I will present the methodological approaches of this study to corpus design and the collection of both the sample corpus and the main corpus used, plus the concordance software tools employed to ←24 | 25→carry out the data analysis in this study. The methodological approach used in this research, i.e. corpus linguistic investigation, will use different concordance tools that capture every aspect of posters. Furthermore, it presents the categories used to identify evidentials in the sample corpus and indicates the conceptual motivations at the basis of my decisions for the inclusion in and exclusion from the investigation of potential evidential items.

Chapters 5 will present the outcomes of manual analysis, based on the theoretical framework presented in Chapter 4. The purpose is to systematically identify evidential markers in a sample corpus. A detailed discussion of the results for each evidential group found by applying Chafe’s (1986) framework and Anderson’s (1986) definition of evidentials to my sample corpus will be carried out too. The results thus obtained are described in detail as input for the main analysis, so as to have a starting point for deciding how to use suitable corpus tools (Wordsmith Tools and WMatrix) to analyse the complete corpus.

Having detected evidential lexical markers in the sample corpus, in Chapter 6 I will expand the list of evidentials by carrying out an automated analysis using two CL tools, namely WordSmith Tools and WMatrix. First, concordance lines of the evidentials found in the sample corpus will be generated with WordSmith Tools and checked against the main corpus, and then contexualized to check for evidentiality in use; second, by using USAS, the semantic annotation tool of WMatrix, I can detect other evidential expressions found in the same semantic field of those evidentials detected in the sample corpus.

Chapter 7 will conduct an investigation, in quantitative and qualitative terms, and will try to see how evidentiality is distributed across the poster sections, and the extent to which, if any, there is a relation between evidentiality use, move rhetorical purposes and the disciplinary tradition.