You are presented with multiple paper abstracts, alongside the associated literature review and chapter titles. Given the provided information, you are going to do a literature review. Please generate a coherent literature review that synthesizes the content, draws connections between different works, highlights major findings, and identifies any gaps in the existing research.

Literature Review Title: Testing L2 Talk: A Review of Empirical Studies on Second-Language Oral Proficiency Testing 
Chapter Title:  OPI Examiner Conduct and Inter-interviewer Variation 
1. Abstract of Cited Paper (BIB001):  The article investigates the behaviour of interviewers during the oral proficiency interview within the framework of the national examination in the English language in Estonia from the gender perspective. The research investigates whether noticeable differences can be traced in the behavioural patterns of male and female interviewers that could lead to placing the candidates in a disadvantaged position, not allowing them to display their language proficiency to the full. The study involves nine female and nine male interviewers whose interview language is subjected to content analysis. The results show an overall attempt to follow the scripted interview format envisaged for this examination, but alterations to the script prevail with both gender groups. DOI: http://dx.doi.org/10.5128/ERYa9.14 
2. Abstract of Cited Paper (BIB002):  Pragmatics is a key domain in language assessment. For more than two decades, advances have been made in conceptualizing the domain, developing assessment instruments, and applying current methods of data treatment to the analysis of test performance. This book, the first edited volume on the topic, brings together empirical studies on a range of well-established and innovative strategies for the assessment of pragmatic ability in a second language. In this introductory chapter, we will first offer an overview of key concepts, situate theoretical models of pragmatic competence within the larger frameworks of communicative language ability and interactional competence, and consider the relationship between pragmatics and language testing. We will then introduce the chapters, organized into two Parts. The chapters assembled in Part I investigate assessment instruments and practices for a variety of assessment constructs, purposes, and contexts, guided by different theoretical outlooks on pragmatics. Part II comprises studies of interaction in different forms of oral proficiency interview, conducted from the perspective of conversation analysis. 
3. Abstract of Cited Paper (BIB003):  Poststructuralist perspectives on the discursive construction of identity and critical approaches to linguistics, discourse analysis, and language testing have contributed to a growing awareness of the complex social nature of performance in speaking tests. In this article, I explore how the concept of co-construction is useful to understand how candidate and interviewer identities are created in the discourse of speaking tests but argue for an expanded notion of co-construction that draws upon the concept of intertextuality to recognise the myriad of other ‘voices’, representing those who craft the tests, are interwoven into the discourses produced. The study adopts a qualitative approach, drawing upon discourse analysis to examine co-construction and intertextuality in two levels of Cambridge speaking tests. The findings reveal how interviewers and candidates co-construct particular identities through their interaction with each other, the interlocutor frame, and the test materials, and this can account... 
4. Abstract of Cited Paper (BIB004):  This paper examines how a standardized question is launched and received in a corpus of performance appraisal interviews, with a focus on how pre-­formulated questions are translated into interaction. Using conversation analysis, we demonstrate that the same question becomes many different actions in practice. Prefaces as well as prosodic and lexical alterations make relevant different responses, and as such, the question can be recruited to initiate diverse interactional projects such as assessments and other socially delicate activities. As a consequence, goals of uniformity and standardization may be subverted. The interactional adaptations further evidence the strength of recipient design as reformulations also result in more fitted and personalized answers. Our study contributes to the understanding of standardization versus interactionalization, and points to the strong interrelationship between question design and the fitting of response options.

Literature Review:
Not surprisingly, a dominant theme for OPI interaction research is examiner conduct and interinterviewer variation (Brown 2005 BIB002  . A number of studies prior to our selected time frame suggest that variations in interviewer strategies play a central role for candidate performance, which is confirmed by Nakatsuhara (2008), who observed that two interviewers who talked to the same candidate exhibited different patterns of questioning, in particular when a question was 'unsuccessful' (270) in eliciting a response. She concludes that the candidate scored better on f luency and pronunciation with the examiner who used a less structured interview style, more so-called receipt tokens, and positive assessments. Similarly, BIB001 identified differences in interviewer styles in two OPIs with the same candidate, which affected the candidate's score. BIB003 investigate interviewer questions. They argue that test-takers are given different conditions regarding topic understanding depending on the interviewer's inclination to pose multiple questions in a single turn or if questions are delivered 'one at time' in a question-answer fashion. In other words, interviewers' question design might 'inject bias into the interview process ' (2067) . The authors recommend a shift in focus in interviewer training from questions as tools for eliciting assessable output to questions as central to candidates' topic understanding and conclude that differences in question design might be crucial for the validity of the OPI (cf. also BIB005 . Closely related to issues of validity are papers that touch upon test standardization, but which do not focus solely on the interviewer's conduct. By way of example, BIB004 shows how interviewer and test-taker locally construct situated identities, displayed in their orientation to different discursive frames, which in turn may compromise standardization.