What is a Systematic Literature Review?

A systematic literature review is a structured, organized and transparent process for identifying, selecting, and critically appraising relevant research studies to answer a specific research question. Systematic reviews apply predefined criteria for selecting studies, assessing their quality, and synthesizing their findings. This rigorous methodology ensures that a literature review is exhaustive and reproducible.

At the heart of a systematic review lies a well-defined protocol that guides the entire process, from the formulation of research questions to the selection and appraisal of relevant studies. This systematic approach contrasts with other literature reviews, which may be conducted more flexibly.

The methods in a systematic literature review are designed to offer a comprehensive textual summary and synthesis of existing research, providing context and background information critical to understanding the broader research landscape. Systematic reviews are essential for informing evidence-based practices and policy decisions, as they consolidate findings from numerous studies and offer a high level of evidence.

A systematic review often follows specific guidelines such as the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) (Page et al., 2020). The guidelines ensure that reviews are conducted rigorously and reported clearly. This facilitates the replication of findings and the assessment of conclusions; while PRISMA primarily focuses on quantitative research, it has extensions like PRISMA-ScR that can apply to qualitative research. Researchers also use the Cochrane Handbook for Systematic Literature Reviews (Higgins et al., 2023) which focuses on detailed guidelines for doing systematic reviews of healthcare interventions.

When to conduct a systematic review?

Systematic reviews are often used in evidence-based research and practice, particularly in environmental science, healthcare, and social sciences. Researchers undertake these reviews to identify gaps in current evidence and suggest areas for further investigation. They are essential in developing guidelines and informing policies by providing nuanced and detailed evaluations of experiences, perceptions, and contextual factors.

Qualitative systematic reviews support grant applications by demonstrating the current state of qualitative knowledge and the need for further exploration. Organizations employ a systematic review methodology to improve practices and interventions. Public health professionals rely on qualitative systematic reviews to assess the effectiveness of interventions and shape strategies that consider the socio-cultural contexts. Regularly updating these reviews ensures that the synthesized qualitative evidence remains current, aiding in more informed and effective decision-making in various disciplines.