Systematic reviews are a kind of literature reviews, which uses a systematic method for collecting secondary data, analytically assess the research studies, and create findings both quantitatively or qualitatively. It is complex research, which aims at identifying, selecting, and synthesizing all the research that is published on a particular topic. Such review sticks to a precise scientific design that is built on reproducible and pre-specified methods. It illustrates knowledge about a particular intervention and shows where knowledge is lacking. It is further used to guide future research. Generally, a systematic review will comprise a search methodology, in which you can store the information about where, when, and how you looked for some data, as well as the information about the people you consulted.
Characteristics of a Systematic Review
- The systematic review describes and assesses forgoing work but does not define precise methods through which the reviewed papers were recognised, selected, and assessed.
- It has a clearly specified set of objectives with pre-defined entitlement criteria for different findings.
- It includes an explicit, reproducible methodology.
- It is a systematic search, which tries to recognise all studies that would meet the entitlement criteria.
- It is a valuation of the legitimacy of the findings of studies, such as through the valuation of risk of bias.
- It is a combination and a systematic presentation of the characteristics and findings of included studies.
- It includes the use of explicit criteria to include or exclude studies.
- It is an explicit method of synthesising and extracting the findings of the study.
- It is comprehensive research to find all the relevant studies.
Steps for conducting a systematic review
The systematic review includes the development of the research question, framing the criteria, searching strategy and database, registration of protocol, and other important elements. It is necessary for you to understand the below presented steps before starting a systematic review. In the below section, we will discuss some quick and easy steps that could help you to review your studies and literatures systematically.
Step 1 – Framing question for review
The issue to be addressed in the review should be stated in an unambiguous, clear, and structured question before starting the review. When the review questions have been agreed, alterations to the procedure should be permitted only if the alternate ways of describing the study designs, interventions, outcomes, or populations become ostensible.
Step 2 – Identifying relevant work
Make sure that the research for the study should be prevalent and multiple resources should be searched without the restriction of any language. The selection criteria of the study should move straight from the review questions, and the reasons for exclusion and inclusion should be recorded properly.
Step 3 – Evaluating the quality of studies
Evaluation of the study quality is applicable to each step of the review. The selected studies should be laid open to a more advanced quality evaluation technique by using the general critical appraisal guidelines and through design-based quality lists. Such detailed quality valuations will be used for discovering heterogeneity and updating decisions concerning the suitability of the meta-analysis. They also help in evaluating the strength of implications and providing recommendations for upcoming research.
Step 4 – Summarising the evidence
Data synthesis includes a tabulation of the characteristics of the study. It also comprises quality and effects along with the use of numerical methods for discovering differences between various studies and linking their effects. It is essential for you to explore the heterogeneity and its sources in advance, and if the overall meta-analysis cannot be done, you can also make sub-groups of the meta-analysis.
Step 5 – Interpreting the findings
Remember to meet all the issues highlighted in the above steps and explore the risk of publication bias and all the other related biases. Make sure that the exploration of the heterogeneity should help in determining the reliability of the complete summary. Clearly present your findings in a manner that your review can be updated easily for new research findings in the future. Also, provide recommendations for filling the existing gap in the research.
It is known that systematic review is one of the most reliable types of study which can be used by researchers in different practising areas. It aims at identifying, evaluating, and summarising the results obtained from all the relevant individual studies and making the evidence available for the decision makers.