Literature review

A literature review is an overview of the previously published works on a topic. The term can refer to a full scholarly paper or a section of a scholarly work such as a book, or an article. Either way, a literature review is supposed to provide the researcher/author and the audiences with a general image of the existing knowledge on the topic under question. A good literature review can ensure that a proper research question has been asked and a proper theoretical framework and/or research methodology have been chosen. To be precise, a literature review serves to situate the current study within the body of the relevant literature and to provide context for the reader. In such case, the review usually precedes the methodology and results sections of the work.

Producing a literature review is often a part of graduate and post-graduate student work, including in the preparation of a thesis, dissertation, or a journal article. Literature reviews are also common in a research proposal or prospectus (the document that is approved before a student formally begins a dissertation or thesis).

A literature review can be a type of review article. In this sense, a literature review is a scholarly paper that presents the current knowledge including substantive findings as well as theoretical and methodological contributions to a particular topic. Literature reviews are secondary sources and do not report new or original experimental work. Most often associated with academic-oriented literature, such reviews are found in academic journals and are not to be confused with book reviews, which may also appear in the same publication. Literature reviews are a basis for research in nearly every academic field.

Types
Since the concept of a systematic review was formalized (codified) in the 1970s, a basic division among types of reviews is the dichotomy of narrative reviews versus systematic reviews. The term literature review without further specification still refers (even now, by convention) to a narrative review.

The main types of narrative reviews are evaluative, exploratory, and instrumental.

A fourth type of review, the systematic review, also reviews the literature (the scientific literature), but because the term literature review conventionally refers to narrative reviews, the usage for referring to it is "systematic review". A systematic review is focused on a specific research question, trying to identify, appraise, select, and synthesize all high-quality research evidence and arguments relevant to that question. A meta-analysis is typically a systematic review using statistical methods to effectively combine the data used on all selected studies to produce a more reliable result.

Torraco (2016) describes an integrative literature review. The purpose of an integrative literature review is to generate new knowledge on a topic through the process of review, critique, and then synthesis of the literature under investigation.

George et al (2023) offer an extensive overview of review approaches and describe six different types of review, each with their own unique purpose. First, the exploratory or scoping review which focuses on broadness as opposed to depth. Second, the systematic or integrative review which integrates empirical studies on a topic. Third, the meta-narrative review which is a qualitative review approach that uses literature to compare different research or practice communities. Fourth, the problematizing or critical review which proposes new ways of thinking about a concept by linking it with other literature. Fifth, the meta-analysis and meta-regression which provide an integration of quantitative studies and identify moderators. And, finally, the mixed research synthesis which combines other review approaches in the same paper. They also propose a model for selecting an approach by looking at the purpose, object, subject, community and practices of the review.

Process and product
Shields and Rangarajan (2013) distinguish between the process of reviewing the literature and a finished work or product known as a literature review. The process of reviewing the literature is often ongoing and informs many aspects of the empirical research project.

The process of reviewing the literature requires different kinds of activities and ways of thinking. Shields and Rangarajan (2013) and Granello (2001) link the activities of doing a literature review with Benjamin Bloom's revised taxonomy of the cognitive domain (ways of thinking: remembering, understanding, applying, analyzing, evaluating, and creating).

Use of artificial intelligence in a literature review
Artificial intelligence (AI) is reshaping traditional literature review across various disciplines. Generative pre-trained transformers, such as ChatGPT, are often used by students and academics for review purposes.

Nevertheless, the employment of ChatGPT in academic reviews is problematic due to ChatGPT's propensity to "hallucinate". In response, efforts are being made to mitigate these hallucinations through the integration of plugins. For instance, Rad et al. (2023) used ScholarAI for review in cardiothoracic surgery.