What is a systematic review of the literature?

By Soumya Srivastava on October 29, 2018
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A systematic literature review attempts ‘to identify, appraise and summarise all the empirical evidence. Evidence must meet pre-specified eligibility criteria to answer a given research question. A systematic review of literature helps to develop the study that allows identification, quality, limitations and potential. Most importantly any significant study must be followed by a comprehensive review of the existing literature based on both qualitative and quantitative data.

The systematic review follows a transparent and rigorous approach. The process must ensure minimum bias and potential replicability as systematic review paves the way for reduced implicit researcher bias.

Steps of conducting a systematic literature review

Steps for conducting systematic literature review
Steps for conducting a systematic literature review

Example: Impact evaluation of Pradhan Mantri Jan Dhan Yojna (PMJDY) on Financial Inclusion in India

In India, the majority of the population is not a part of inclusive growth. Therefore, financial inclusion is a major challenge. The purpose is to provide banking services to all households. Pradhan Mantri Jan Dhan Yojana is a scheme launched in India. It aims at providing banking services and financial independence to the unbanked in India.

Clearly define the research questions

The first step to conducting a systematic literature review is to formulate a clear and well-defined research question. It is very important to find the existing literature on the topic because your study should not duplicate the efforts of previous reviews. Research questions must be based on PICO analysis:

  1. Person: who does this relate to?
  2. Interventions: what is the probable cause or intervention?
  3. Comparison: Is the cause comparable to something?
  4. Outcome: What is your expected outcome or outcome you are interested in?

In the example taken above the research, question is, “What is the impact of PMJDY on the financial inclusion in India?”

Frame the protocol for review

Second, in order to select various studies for the research, the researcher must stick to certain protocols. Protocols inhibit the inclusion and exclusion criteria for the selection of relevant studies because this helps in determining whether to include the study in the research for review or not. Search strategy on basis of finding the words or the set of words must be followed.

For the purpose of the above example, the inclusion and exclusion criteria have been summarized as below:

Flowchart on selection criteria
Flowchart on selection criteria

Conduct a literature review

Thirdly, start the search in the database that you identify as relevant to your topic. Work on the search strategy across a variety of databases. The researcher can probably identify the relevant papers by screening the title and the abstract, at last, the researcher rejects those which are not fulfilling the inclusion criteria. 90 research studies are part of the present research for the systematic review of the literature.

Select specific studies

Fourth, move ahead along with the protocols. According to the inclusion and exclusion criteria, the researcher will be able to select specific studies relevant to the topic. Then, start with the screening of the title and probably go to the abstract to evaluate a particular study. Furthermore, multiple screenings must take place for the review. 15 studies out of 90 search studies are part of the present research.

The following figure is the flowchart of studies for systematic review:

Flowchart of Systematic Review
Flowchart of Systematic Review

Extract data or qualitative information from selected studies

Fifth, an MS-Excel spreadsheet can be of use to extract data from the existing literature. Besides that, the systematic review tool can be of use. Then, analysing of the data for the purpose of addressing the research questions takes place. In our case the time series data on the number of bank accounts, the number of non-frill accounts and cash balance in banks is part of the data for the purpose of analysis. The results will be able to address the research objective of evaluating the impact of the PMJDY scheme on financial inclusion in India. Qualitative data inheriting the characteristics of the scheme is also a part of the study.

Assess the quality of the study

Sixth, the quality of the selected studies must be part of the assessment. It can assess the following parameters:

  1. Appropriateness of the study
  2. Risk of bias
  3. Quality of issue and intervention

Summarise the evidence or data

Summarising the data involves the tabulation of the study details, characteristics, quality and effects. The table must include the identified factors. The table includes the relationship with the concerned variable. In the present topic, 15 studies were systematically taken, the table includes the author details and the publishing dates of the studies. Apart from this, the table has the identified factors from each study. Following are the factors of the present study:

  1. Total paper transactions
  2. Digital transaction amount
  3. Zero-balance accounts
  4. The total balance in an account
  5. Number of debit cards
  6. A share of digital services

Discuss the findings and conclude

Finally, present your finding in a well-defined manner with a detailed methodology. Also, provide the recommendations for practice.

The PMJDY scheme has proven to be beneficiary to India thus, an unbanked proportion significantly decreased. Zero balance accounts were falling as people were depositing their money into the banks. Almost all the money deposits in the bank translate into capital formation when channelises as savings and investment, therefore it leads to economic as well as inclusive growth.