systematic review vs literature review

systematic review vs literature review

Differences between Systematic Review and Literature Review

1. Introduction

In the field of learning, there are various types of review that can be used as a method. But for this opportunity, we focused on discussing two types of review, systematic review and literature review. In conducting a review, a critical aspect has to be taken into consideration by the researcher for making a decision. Yaqub (2016) mentioned a review will be helpful while trying to choose the best available evidence needed for preparing a clinical practice guideline. By producing a review, it will facilitate medical professionals to make health policies and clinical decisions. Both systematic review and literature review have their own strength and characteristics that differentiate each other. Hence, this paper tries to discuss both reviews from the context of their objective, process until the number of studies needed for conducting it.

2. Definition of Systematic Review

When a systematic review follows these methods it is of unparalleled value to informing clinical practice and policy. A systematic review employing these methods allows for a minimization of bias, and in understanding bias in the primary studies it can be identified and explained in the review. This is particularly important as health care decisions should be based upon evidence of the best possible quality. Any type of review should provide evidence for its conclusions and this is particularly true of systematic reviews, as without evidence it cannot be established that bias has been minimized and errors in the review have not been made.

The Cochrane tool and this methodology can be generalized to other types of systematic reviews.

Systematic reviews can be of many different types of studies, such as randomized controlled trials, but not all systematic reviews are limited to clinical trials. A well-known example is the Cochrane Review, which can be a gold standard in evidence-based health care. Step 2 of the Cochrane handbook outlines the plan of the systematic review: a protocol for the review must first be prepared, then a method to locating and selecting studies, collecting data, and finally an analysis of the data in order to answer the research question must be conducted.

A systematic review attempts to collate all empirical evidence that fits pre-specified eligibility criteria in order to answer a specific research question. It uses explicit, systematic methods that are selected with a view to minimizing bias, thus providing more reliable findings from which conclusions can be drawn and decisions made. These are fundamental characteristics of a systematic review. We identify, assess and synthesize the findings of similar studies. These findings may have been derived from primary studies that are published or unpublished. Cochrane Collaboration’s tool for conducting systematic reviews is the best place to look for detailed and validated guidance to help you conduct a systematic review. Systematic reviews are also used to compare the effects of different interventions, and provide evidence to support or disprove a hypothesis aetiology.

3. Definition of Literature Review

A literature review is an evaluative report of information found in the literature related to the selected area of study. The review should describe, summarise, evaluate, and clarify this literature. It should give a theoretical base for the research and help you (the author) determine the nature of your research. Works which are irrelevant should be discarded, and those which are peripheral should be looked at critically. A literature review is more than an annotated bibliography or a list of separate, related articles. It will give an overall picture of the information and the point of view of those writing on the topic. Frequently, it will compare previous studies with your current study and identify ‘gaps’ in the literature which your research can attempt to fill. Because of its systematic and precise procedure, a literature review provides a very credible source of research. This can be evidenced through the abundance of references to previous studies found in your average academic article. Writing a literature review is possibly the best piece of literature that a student can work with. This is because writing a literature review only means that you are already near the end of your final requirement in your student life, which is either a thesis or even a dissertation.

4. Key Differences

A systematic review is a form of analysis that medical researchers carry out to synthesize all the available evidence on a particular question, such as how effective a drug is. A good systematic review will not only find all the controlled trials, but will also look for methodological studies of these trials. A well-done systematic review will provide an exhaustive, comprehensive summary of current literature relevant to a research question. The question must be precisely defined, and should be the guide for the research. All aspects of the review, including methods to be used in identifying and assessing studies, criteria for making decisions and data extraction should be laid out in advance. Systematic reviews should be unbiased, thorough, and reproducible. The goal of a systematic review is to create a meticulous, comprehensive, and exhaustive summary of current literature relevant to the research question.

A literature review is a piece of discursive prose, not a list describing or summarizing one piece of literature after another. It’s usually a bad sign to see every paragraph beginning with the name of a researcher. Instead, organize the literature review into sections that present themes or identify trends, including relevant theory. You are not trying to list all the material published, but to synthesize and evaluate it according to the guiding concept of your thesis or research question. If you are writing an annotated bibliography, you may need to summarize each item briefly, but should still follow through themes and concepts and do some critical assessment of material. Use an overall introduction and conclusion to state the scope of your coverage and to frame your material.

5. Conclusion

A contradicting view is argued by Tranfield et al (2003) that in the realm of evidence-based research, there is a general shift towards the systematic review of research. This has resulted in the term literature review being saddled with the connotation of a less rigorous and therefore less relevant form of review. Its more cost-effective (Bowling, 2005), measure of quality, and ability to present evidence are factors that have seen systematic review viewed as the superior method of review. This has led to the wider-ranging comparison of effectiveness between the two types of review. Shim et al (2010) assert that given the changes to traditional literature reviews and the variety of methods and approaches from different authors, there is a need to compare the validity of the two methods. This is a view supported by Slobogean, Verma, Giustini, and Slobogean (2010) and Taiwo et al (2013) who attempted to compare the quality of systematic reviews and literature reviews through rating and comparing their objectives. These comparisons mark an important step in determining whether systematic and literature reviews are indeed different and whether systematic review is superior to the traditional literature review.

Melia (2001) argues that there should be no confusion between the two, as systematic review uses a wider range of material, much of it published in a non-conventional format, such as reports and conference proceedings. It may also involve looking at sources of which there are no controlled studies, for example research into health beliefs and values. Additionally, the objectives of systematic review are quite different compared with many literature reviews. This can be exemplified in the Cochrane collaboration’s handbook (Higgins and Green, 2011), which is largely considered the definitive source of guidance on conducting a systematic review and meta-analysis. It is over 700 pages long with 11 chapters, significantly more detailed than any guidance on writing a literature review. The objectives of systematic review are to identify, evaluate, interpret, and synthesize all research evidence relevant to a research question. This is compared to the more limited objective of literature review to identify and synthesize only the findings of research that are relevant to the research question.

Literature review and systematic review have had several rapid flurries in the last ten years. Are they different types of review? Is systematic review simply a literature review that is systematic in approach, or is systematic review a genre within itself? (Morrison, 1997) The following concluding thoughts aim to outline the debates around these questions.