Service overview
Twenty review formats, from systematic and scoping reviews to meta-analyses and landscape reviews. This service is part of that division and is scoped individually around what you need to learn, decide or publish.
An umbrella review synthesises evidence from existing systematic reviews and meta-analyses. It is used when many reviews exist on a topic, sometimes with overlapping or conflicting conclusions, and readers need an overview. Umbrella reviews are common in medicine and are increasingly proposed in engineering fields that have matured to the point of having multiple systematic reviews.
Their special difficulty is overlap: the same primary study may be included in several reviews, so counting reviews can overstate the amount of independent evidence. The quality of the included reviews also varies. Support concentrates on review-level search and selection, overlap assessment, appraisal of reviews and a careful synthesis of review-level conclusions.
What this service covers
Problems this service can address
- Overlapping primary studies across reviews
- Variable quality of included reviews
- Heterogeneous outcome reporting
Methods and analytical approaches
- Review-level search and selection
- Overlap assessment concepts
- Quality appraisal of reviews
- Synthesis of review-level conclusions
Applications
- High-level evidence summaries
- Policy and guideline background
- Research-prioritisation papers
Relevant engineering disciplines
Scope, inputs and deliverables
Scope of work
- Assessment of your material: data, methods, draft and target venue
- Structuring and drafting or editing strictly from your supplied results and methods
- Consistency and source checks on text, tables, figures and references
- Journal-formatted files and a submission checklist
- Feasibility check on: candidate reviews or a search
Typical inputs required from you
- Candidate reviews or a search
- Question and scope
- Appraisal approach
Deliverables
- Umbrella-review manuscript
- Overlap and quality tables
- Reporting checklist
Highly specialised requests are first checked for feasibility from this information. Please do not send confidential data through the public form; describe it first and agree secure transfer afterwards.
Project workflow and method
- 01Enquiry and requirement assessment
- 02Technical scoping and proposal
- 03Execution
- 04Quality review and delivery, with an agreed round of revisions
Read the full project workflow.
In depth: how the work is done
When an umbrella review is appropriate
An umbrella review makes sense when several systematic reviews address related questions and a higher-level summary adds value. If there are only one or two reviews, a different approach may be better. We help authors judge whether the field has enough reviews and define a question at the right level.
Review-level search and selection
The search targets systematic reviews and meta-analyses, using filters and terms for review types. Eligibility criteria require that included reviews used systematic methods. The selection process is reported with a flow diagram, and decisions about borderline reviews are explained.
Assessing and handling overlap
Overlap is assessed by building a citation matrix showing which primary studies appear in which reviews, and by calculating measures such as corrected covered area. High overlap calls for caution in interpretation, and options include selecting the most recent or highest-quality review for each question. The manuscript states how overlap was handled.
Appraising the quality of included reviews
Tools exist for appraising systematic reviews, assessing aspects such as protocol registration, search comprehensiveness, risk-of-bias assessment and appropriateness of synthesis. Where tools designed for health are adapted for engineering, adaptations are explained. Low-quality reviews are treated cautiously.
Extracting and synthesising review-level conclusions
Data extracted include review aims, included studies, methods, key findings and certainty. Synthesis compares conclusions across reviews, highlighting consistency and conflict, and tries to explain differences by scope, date, included studies or methods. Re-analysis of primary data is outside the usual scope.
Presenting results
Tables of reviews, overlap matrices and summary figures should be clear. Consistent grading of certainty helps readers. We help authors present complex information compactly.
Limitations specific to umbrella reviews
Umbrella reviews inherit the limitations of the included reviews, may miss recent primary studies and rely on reviewers' judgements. Stating these prevents overinterpretation.
Reporting guidance for umbrella reviews
Umbrella reviews borrow from PRISMA and, in health, from dedicated guidance. Whatever guideline is followed should be named, and items that do not apply should be explained. Typical additional items include the handling of overlap, appraisal of reviews and how conflicting conclusions were reconciled. We help authors map their manuscript to the relevant checklist and complete missing details.
Deciding when not to proceed
Sometimes the right outcome of scoping an umbrella review is to decide against it: too few reviews, reviews of poor quality or questions too different to compare. Reporting such a decision in a short methods note or using the material for a different type of review is legitimate. We help authors recognise these situations early and choose a more suitable review design.
Presenting review-level evidence to decision makers
Umbrella reviews are often intended for readers who need a summary and not a detailed methods account. A clear summary table that lists each question, the number of independent reviews addressing it, the consistency of findings and the certainty of evidence helps these readers. We help authors design a summary that is accurate and not oversimplified, with methods details available in supplementary material.
Quality control and good practice
Quality-control approach
- Every statement, number and reference is checked against your supplied data and the original sources.
- No data, results, citations or author contributions are invented; gaps are flagged to you.
- Authorship and contribution decisions stay with you and your co-authors, and the use of AI tools is disclosed where journals require it.
- Journal guidelines and reporting checklists are followed; acceptance is never promised.
Common pitfalls this service helps avoid
- Counting reviews as independent evidence. Overlap inflates apparent support.
- Including non-systematic reviews. Inclusion criteria must ensure systematic methods.
- Ignoring review quality. Poor reviews can mislead the synthesis.
- Stale conclusions. Recent primary studies may not be captured.
What good reporting looks like
Support for an umbrella review is documented with a review-selection flow record, an overlap matrix check, an appraisal-tool description and a limitations list. The authors conduct the review and synthesis. We do not invent reviews, data or conclusions, and we do not promise acceptance.
An illustrative scenario
Hypothetical example written for explanation. It is not a client case, a result or a testimonial.
Suppose a team collects eight systematic reviews on machine-learning prediction of material properties. The citation matrix shows heavy overlap among five of them. The synthesis explains that agreement among reviews largely reflects the same underlying studies, so the effective evidence is smaller than eight reviews suggest. The manuscript presents conclusions with that qualification.
Questions to settle before you begin
- Do enough systematic reviews exist for an umbrella review?
- How much primary-study overlap exists?
- Which reviews are of low quality?
- Why do reviews disagree?
- How recent are the primary studies?
Key terms
- Umbrella review
- A review of systematic reviews.
- Corrected covered area
- A measure of overlap among reviews.
- Citation matrix
- A table showing which studies appear in which reviews.
- AMSTAR-type tool
- An instrument for appraising systematic reviews.
- Certainty of evidence
- Confidence in a body of evidence.
Working together on Review Article Writing projects
Review article engagements begin by choosing the review type that fits the question, because systematic, scoping, narrative and bibliometric reviews have different methods and reporting expectations. We ask for the topic, the target journal and any searches or papers you already have. The method is documented so that the review can be audited, and every source cited is checked against the original. We do not invent references or studies, and we state limitations such as database coverage. Acceptance depends on editors and reviewers and cannot be promised.
Frequently asked questions
When is an umbrella review feasible?
When enough systematic reviews exist on the topic. We check this early so effort is not wasted.
Are umbrella reviews common in engineering?
Less so than in medicine, but increasing in mature topics.
How do I handle overlapping studies?
Assess overlap with a citation matrix and report how it was addressed.
Can you help calculate overlap measures?
We can explain the methods and help present results. Calculations use data prepared by the authors.
Is a protocol needed?
Yes, as for other systematic approaches.
Does ENGRexpert guarantee acceptance in a journal?
No. Editors and reviewers decide. We support the clarity, rigour and fit of your manuscript and never promise an outcome.
How is this service scoped and priced?
After your enquiry we review what you need, ask for missing information and send a written scope and quotation. Price depends on complexity, deliverables and timeline. See the project workflow.