Evidence Synthesis in the Social Sciences

Systematic Review VS Scoping Review

Systematic reviews and scoping reviews are both types of literature reviews used in research, but they serve different purposes and have distinct methodologies.

Categories	Systematic Review	Scoping Review
Purpose	Conducted to answer a specific research question by synthesizing the available evidence from primary studies. The focus is on providing a comprehensive and unbiased summary of existing research to inform practice or policy.	Aimed at mapping the existing literature on a broader topic without necessarily addressing a specific research question. It helps to identify gaps in the literature, clarify concepts, and provide an overview of the available evidence.
Research Question	Has a well-defined research question or set of questions that guide the review process. The goal is to answer these questions systematically.	Typically begins with a more general or broad research question. The objective is to explore the extent, range, and nature of the existing literature on a topic.
Study Selection	Inclusion criteria are defined very specifically to ensure the selected studies are directly relevant to the research question. Rigorous eligibility criteria are applied during study selection.	Inclusion criteria may be broader, allowing a wide range of study types, including both empirical and non-empirical literature. The focus is on comprehensiveness rather than specificity.
Data Extraction and Synthesis	Involves a rigorous and systematic process of screening and selecting studies based on predefined criteria. This process is often conducted by multiple reviewers independently to ensure objectivity.	Typically involves a more iterative and flexible process of study selection. It may include a broader range of literature, and the selection process may be less rigid.
Reporting Standards	Adheres to specific reporting standards such as PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses).	Reporting standards may vary, and there isn't a universally accepted guideline. However, the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews).
Indications	Uncover the international evidence Confirm current practice/ address any variation/ identify new practices Identify and inform areas for future research Identify and investigate conflicting results Produce statements to guide decision-making	To identify the types of available evidence in a given field To clarify key concepts/ definitions in the literature To examine how research is conducted on a certain topic or field To identify key characteristics or factors related to a concept As a precursor to a systematic review To identify and analyse knowledge gaps
Example	Loong, D., Bonato, S., Barnsley, J., & Dewa, C. S.(2019). The effectiveness of mental health courts in reducing recidivism and police contact: A systematic review. Community Mental Health Journal, 55, 1073-1098. doi: 10.1007/s10597-019-00421-9	Langevin, R., Marshall, C., & Kingsland, E. (2021). Intergenerational Cycles of Maltreatment: A Scoping Review of Psychosocial Risk and Protective Factors. Trauma, Violence, & Abuse, 22(4), 672–688. https://doi.org/10.1177/1524838019870917

Defining characteristics of traditional literature reviews, scoping reviews and systematic reviews (Smith et al, 2022; Munn wt al., 2018)

Essential Resources

Munn, Z., Peters, M.D.J., Stern, C. et al. Systematic review or scoping review? Guidance for authors when choosing between a systematic or scoping review approach. BMC Med Res Methodol 18, 143 (2018). https://doi.org/10.1186/s12874-018-0611-x

Covidence: Difference between Systematic and Scoping Review

Smith SA, Duncan AA. (2022) Systematic and scoping reviews: A comparison and overview. Semin Vasc Surg. (4):464-469. doi: 10.1053/j.semvascsurg.2022.09.001