A 6-Step Guide For A Systematic Literature Review Methodology

What is a Systematic literature review Methodology?

A systematic literature review methodology is a structured and comprehensive approach to identifying, evaluating, and synthesizing relevant research studies on a specific topic or research question. The systematic literature review methodology involves conducting a systematic search across multiple databases, assessing the quality of identified studies, extracting relevant data, and synthesizing the findings through meta-analysis or other quantitative or qualitative techniques.

This rigorous methodology aims to minimize bias and provide a comprehensive overview of the existing evidence on a particular research question. Key steps in the systematic literature review methodology include defining the research question, developing a search strategy, identifying relevant studies based on predetermined inclusion and exclusion criteria, assessing the quality of included studies, extracting data, conducting meta-analysis or other synthesis methods, and reporting the findings following guidelines such as the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

When to use a Systematic Literature Review Methodology?

A Systematic Literature Review Methodology should be used in the following situations:

1. To synthesize evidence from multiple research studies on a specific research topic or question.

• It provides a comprehensive and unbiased overview of the available literature by systematically identifying, evaluating, and synthesizing relevant studies.

2. To identify research gaps and future research directions in a particular field or research area.

• By critically analyzing the existing literature, a systematic review can reveal gaps in knowledge and inform future research priorities.

3. To inform evidence-based practice, guidelines, or policy decisions.

• Systematic reviews provide a solid foundation for evidence-based decision-making by rigorously evaluating and synthesizing the best available evidence.

4. To conduct a meta-analysis or quantitative synthesis of research findings.

• A systematic review is often a prerequisite for meta-analysis, as it involves identifying and evaluating all relevant studies on a topic.

5. When there is a need for a comprehensive and transparent review process.

• The systematic literature review methodology follows a clearly defined and replicable process, ensuring transparency and minimizing bias.

6. To assess the quality and strength of the evidence in a research area.

• Systematic reviews typically include a quality assessment or risk of bias evaluation of the included studies, providing insights into the robustness of the evidence.

7. When there is a need to synthesize qualitative or mixed-methods research studies.

• Although initially developed for quantitative research, the systematic review methodology has been adapted for qualitative and mixed-methods studies as well.

8. To identify and address potential publication bias in a research area.

• Systematic reviews aim to include both published and unpublished (gray literature) studies, helping to mitigate publication bias.

9. To establish a comprehensive knowledge base for a new or emerging research topic.

• Systematic reviews can be particularly valuable in consolidating the existing knowledge on novel or rapidly evolving research areas.

10. To update and synthesize the latest evidence in a field with rapidly expanding literature.

• Systematic reviews can be periodically updated to incorporate new evidence and ensure that decision-making is based on the most current knowledge.

What are the Advantages of Systematic Literature Review Methodology?

The Systematic Literature Review Methodology offers several advantages:

• Comprehensive Search: The systematic review approach involves a thorough and systematic way of collecting and identifying the relevant literature through formulated research questions and specific search terms across multiple databases like Web of Science.
• Unbiased Selection: Clearly defined inclusion and eligibility criteria ensure that all relevant research articles and studies are included in the review, minimizing potential publication bias or exclusion of gray/grey literature.
• Quality Assessment: A critical appraisal and quality assessment of the included research studies are conducted, following guidelines like the PRISMA Statement (Preferred Reporting Items for Systematic Reviews and Meta-Analyses).
• Evidence Synthesis: The systematic review methodology allows for the synthesis of qualitative and quantitative research findings from multiple research studies through narrative reviews, meta-analyses, or other statistical techniques.
• Research Gap Identification: By critically analyzing the current literature, systematic reviews can identify gaps in knowledge and inform future research directions within a specific research discipline or area.
• Evidence-Based Practice: The rigorous evaluation and synthesis of evidence make systematic reviews valuable for informing evidence-based practice, management research, and decision-making in various research fields.
• Meta-Analysis Facilitation: Systematic reviews often serve as a foundation for conducting meta-analyses, which provide quantitative summaries of the pooled effect sizes across studies.
• Transparency and Replicability: The systematic review approach follows an explicit and systematic method and process, making it transparent and replicable by other researchers.
• Research Credibility: The systematic nature of the methodology enhances the credibility and reliability of the research findings, contributing to the advancement of knowledge by means of systematic review.
• Collaboration and Knowledge-Sharing: Systematic reviews often involve multidisciplinary teams, promoting collaboration and knowledge-sharing among researchers from different fields.
• Knowledge Consolidation: By systematically synthesizing the existing literature, systematic reviews provide an efficient way to consolidate and disseminate knowledge in a particular research area or topic.
• Evidence Updates: Systematic reviews can be updated periodically to incorporate new research articles and studies, ensuring that decision-making is based on the most current available literature and evidence.

What are the Disadvantages of Systematic Literature Review Methodology?

The Systematic Literature Review Methodology, while offering several advantages, also has some potential disadvantages:

1. Time and Resource Intensive: Conducting a systematic review is a rigorous and proper research process that requires a significant investment of resources, including a dedicated team of researchers to perform the actual review work.
2. Narrow Scope: The strict inclusion criteria used in systematic reviews may result in a narrow scope, potentially excluding relevant literature that does not meet the predefined eligibility criteria, limiting the comprehensiveness of the review.
3. Difficulty with Emerging Topics: For emerging or rapidly evolving research areas, conducting a systematic review can be challenging, as the available literature may be limited, and the included studies may not fully capture the most recent developments or findings.
4. Publication Bias: Despite efforts to include gray/grey literature, systematic reviews may still be influenced by publication bias, where studies with positive or significant results are more likely to be included in the review.
5. Qualitative Study Synthesis: Synthesizing qualitative or mixed-methods studies can be difficult due to the diverse methodological approaches and reporting styles employed in these types of research articles.
6. Limited Generalizability: The findings and conclusions of a systematic review may have limited generalizability beyond the specific research question or context examined, particularly if the included studies have narrow inclusion criteria.
7. Researcher Bias: Despite efforts to minimize bias, the systematic review process may still be influenced by the subjective decisions and judgments made by the review team, such as the selection of search terms, inclusion criteria, and quality assessment tools.
8. Rapidly Evolving Literature: For research areas with a large number of literature or rapidly evolving literature, conducting a comprehensive systematic review can be challenging, as the review may quickly become outdated.
9. Lack of Consensus on Methods: In some fields or types of research, there may be a lack of consensus or established guidelines on the methodological approach or best practices for conducting systematic reviews, which can impact the quality and consistency of the review process.
10. Difficulty in Combining Studies: Depending on the heterogeneity of the included studies, combining and synthesizing the findings from different research designs, sample sizes, and methodological approaches can be a challenge, potentially limiting the conclusions that can be drawn from the systematic review.

How to Conduct a Systematic Literature Review Methodology in 9 Steps

Conducting a Systematic Literature Review Methodology is a rigorous and comprehensive process that involves several steps to ensure a thorough and unbiased synthesis of the existing research evidence on a specific topic or research question. The following nine steps outline a detailed approach to conducting a systematic literature review:

Step 1: Formulate the Research Question(s)

• The first and most critical step in the systematic literature review methodology is to clearly define the research question(s) or objectives that the review aims to address. A well-formulated research question will guide the entire review process, including the search strategy, inclusion and exclusion criteria, and data extraction and synthesis.
• The research questions of the Systematic Literature Review Methodology should be specific, focused, and aligned with the review’s purpose. It is often helpful to use a framework such as PICO (Population, Intervention, Comparator, Outcome) or PIO (Population, Intervention, Outcome) to structure the research question precisely.
• Example research question: “What is the effectiveness of mindfulness-based interventions in reducing anxiety symptoms among adults with generalized anxiety disorder compared to cognitive-behavioral therapy or standard care?”

Step 2: Develop the Search Strategy

• The next step is to develop a comprehensive and systematic search strategy for the Systematic Literature Review Methodology to identify all relevant literature related to the research question(s). This involves selecting appropriate databases, defining search terms and keywords, and combining them using Boolean operators (AND, OR, NOT).
• It is essential to consult with subject matter experts, librarians, or information specialists to ensure the search strategy is comprehensive and captures all relevant literature. Additionally, using controlled vocabularies or thesauri specific to the databases can improve the search accuracy.
• The search strategy should be documented in detail, including the databases searched, search terms used, and any limitations or filters applied (e.g., publication dates, language restrictions).

Step 3: Define Inclusion and Exclusion Criteria

Clearly defined inclusion and exclusion criteria in Systematic Literature Review Methodology are crucial for ensuring the relevance and quality of the studies included in the systematic review. These criteria should be based on factors such as:

• Population or participant characteristics
• Types of interventions or exposures
• Comparator or control groups
• Outcome measures of interest
• Study designs (e.g., randomized controlled trials, observational studies)
• Publication dates
• Language restrictions
• Publication status (published or unpublished/gray literature)

The inclusion and exclusion criteria should be determined a priori and consistently applied during the study selection process to minimize bias and ensure transparency.

Step 4: Conduct the Literature Search

• With the search strategy and inclusion/exclusion criteria defined, the next step is to conduct the comprehensive literature search across the identified databases and other relevant sources (e.g., reference lists, hand-searching journals, contacting experts).
• It is recommended to follow the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for reporting the search process, including the number of records identified, duplicates removed, and studies screened and assessed for eligibility in the Systematic Literature Review Methodology.

Step 5: Study Selection and Screening

• The study selection process in the Systematic Literature Review Methodology typically involves two stages: an initial screening of titles and abstracts, followed by a full-text review of potentially relevant studies.
• During the initial screening, two or more independent reviewers should assess the titles and abstracts against the predefined inclusion and exclusion criteria. Any disagreements should be resolved through discussion or by consulting a third reviewer.
• The full-text review stage involves retrieving and thoroughly examining the full texts of the potentially relevant studies to determine their eligibility for inclusion in the systematic review. This process should be documented, including reasons for exclusion of studies.

Step 6: Data Extraction and Quality Assessment

• For the included studies, relevant data should be extracted using a standardized data extraction form or tool. The data extracted may include study characteristics (e.g., authors, publication year, study design), participant characteristics, intervention details, outcome measures, and results.
• Additionally, a critical appraisal of the methodological quality in Systematic Literature Review Methodology or risk of bias of the included studies should be conducted using appropriate critical appraisal tools or checklists specific to the study designs (e.g., Cochrane Risk of Bias Tool for randomized trials, Newcastle-Ottawa Scale for observational studies).
• It is recommended to have two independent reviewers perform data extraction and quality assessment to minimize errors and bias.

Step 7: Data Synthesis and Analysis

• The extracted data should be synthesized and analyzed using appropriate methods, depending on the nature of the research question(s) and the heterogeneity of the included studies.
• For quantitative data, meta-analysis techniques may be employed to combine and statistically analyze the results from multiple studies, providing a pooled estimate of the effect size and confidence intervals.
• For qualitative or mixed-methods studies, narrative synthesis or other qualitative synthesis methods (e.g., thematic analysis, meta-ethnography) may be used to integrate and interpret the findings.
• Subgroup analyses, sensitivity analyses, and assessments of publication bias (e.g., funnel plots, Egger’s test) can also be conducted to explore potential sources of heterogeneity and bias.

Step 8: Interpret and Report the Findings

The synthesized evidence should be interpreted in the context of the research question(s) and objectives, taking into account the quality and limitations of the included studies.

The findings should be reported in a clear and structured manner, following established reporting guidelines such as the PRISMA statement. The report should include:

• A detailed description of the search strategy, study selection process, and data extraction and synthesis methods
• Characteristics of the included studies (e.g., study designs, populations, interventions)
• Results of the quality assessment or risk of bias evaluation
• Presentation of the synthesized findings (e.g., narrative synthesis, meta-analysis results, forest plots)
• Discussion of the strengths and limitations of the review
• Implications for practice, policy, or future research

Step 9: Update the Review

• In rapidly evolving or emerging research areas, it may be necessary to periodically update the Systematic Literature Review Methodology to incorporate new evidence as it becomes available. This step involves repeating the literature search, screening, and data extraction processes to identify and include relevant new studies.
• Updating the review can help ensure that decision-making and practice recommendations are based on the most current and comprehensive evidence available.
• It is important to note that conducting a Systematic Literature Review Methodology is a resource-intensive and time-consuming process, often requiring a team of researchers with expertise in the subject matter, methodology, and critical appraisal. Adhering to established guidelines and protocols, such as the PRISMA statement and the Cochrane Handbook for Systematic Reviews, can help ensure the rigor, transparency, and reproducibility of the review process.

Frequently Asked Questions about Systematic Literature Review Methodology