Frequently Asked Questions
Questions about our systematic review service — methodology, databases, timeline, pricing, and what you receive.
About Systematic Reviews
What is a systematic review?
A systematic review is a structured, reproducible literature synthesis that identifies and integrates all available evidence on a defined research question. Unlike narrative reviews, a systematic review follows a predefined protocol — specifying the databases searched, the search strategy, and the inclusion and exclusion criteria — so that another researcher could replicate the search and reach the same results. Most peer-reviewed journals require that literature reviews submitted as original research meet systematic review standards, typically documented using the PRISMA reporting guidelines.
What does 'PRISMA 2020 compliant' mean?
PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) 2020 is the international reporting standard for systematic reviews. A PRISMA-compliant document includes a flow diagram showing how articles were identified, screened, and included; a methods section documenting the search strategy, databases, and dates; and a structured results section. Journals and grant reviewers use PRISMA compliance as a minimum quality bar. Every review we deliver is structured to meet PRISMA 2020 requirements.
What does '90% submission-ready' mean?
The document we deliver contains all required sections — abstract, introduction, methods, results, discussion, conclusions, and a complete reference list — structured per PRISMA 2020 guidelines. What remains for you to complete: the structured risk of bias table (a judgment-based assessment requiring clinical expertise), any statistical meta-analysis if your target journal requires it, and your own clinical interpretation in the discussion where journals expect author voice. These tasks require your expertise and cannot be completed on your behalf.
Who conducts the review?
Every systematic review is conducted by a qualified researcher with relevant domain expertise — medical doctors, PhD researchers, postdoctoral fellows, or advanced graduate students supervised by senior reviewers. Reviewers are matched to your topic based on subject-area knowledge. Every completed review undergoes a quality check before delivery.
Search Strategy & Database Coverage
Which databases do you search?
We search three complementary databases: MEDLINE/PubMed (35M+ biomedical and clinical records — the global standard for clinical literature), OpenAlex (260M+ works across all academic disciplines, including journals not indexed by PubMed), and ClinicalTrials.gov (500,000+ registered clinical trials, capturing ongoing and unpublished trial results). Together these cover approximately 97% of published biomedical literature.
Why PubMed + OpenAlex + ClinicalTrials.gov instead of EMBASE and Cochrane CENTRAL?
Traditional systematic review guidelines recommended PubMed, EMBASE (Elsevier), and Cochrane CENTRAL. EMBASE requires a commercial license ($5,000–$20,000/year), which is why many researchers and institutions cannot access it. Peer-reviewed comparison studies show that OpenAlex achieves equivalent or superior recall to EMBASE at no cost. Cochrane CENTRAL has no public search API and largely re-indexes PubMed and EMBASE records, so our stack captures the same literature without licensing overhead. ClinicalTrials.gov adds a category of evidence — registered but unpublished trials — that none of the traditional three databases cover adequately.
Will journals accept a systematic review using these databases?
Yes. Journals evaluate systematic reviews based on coverage breadth, documentation of the search strategy, and compliance with reporting standards — not on which specific databases were used. Our search covers approximately 97% of published biomedical literature. Every query string and search date is included in your methods section, and the PRISMA flow diagram documents exactly how many records were retrieved, screened, and included. Reviewers will have everything needed to assess your search strategy.
Is the search reproducible?
Yes. Your deliverable includes the exact Boolean query strings used for each database, the names of the databases searched, and the dates the searches were run. This meets the reproducibility requirements in PRISMA 2020 and Cochrane Handbook guidance. Any researcher running the same queries on the same databases on the same date would retrieve the same articles.
Process & Ordering
How do I get started?
Contact us with your research question. You do not need a fully formalized PICO at this stage — a plain-language description of your topic is sufficient. We will formalize the PICO, develop the search strategy, and return it to you for approval before running any searches.
What do I need to provide?
Your research question and any specific requirements — target journal, scope constraints, population of interest, or particular study designs to include or exclude. If you have articles you have already sourced, you can provide them and we will include them alongside our search results.
Can I see the article list before committing to the full review?
Yes. After the search is complete, we deliver a ranked article list — every retrieved article with title, authors, journal, year, and relevance score — before you approve the full review. You set the relevance cutoff, which determines the final article set and the cost. Nothing proceeds to full synthesis without your explicit approval.
Can I add articles I already have access to?
Yes. Upload any articles you have already sourced and we will include them in the analysis alongside our database search results. They will appear in the final article list and be treated identically to retrieved articles.
What if I want to adjust the search scope or parameters?
You can request a revised search with adjusted parameters at the scope confirmation stage — before you approve the article list and before the full review synthesis begins. Revisions to scope after synthesis has started may incur an additional fee depending on the extent of the change.
Timeline & Pricing
How long does a systematic review take?
Most reviews are delivered within 5–10 business days of scope confirmation. For comparison, a traditional manual systematic review typically takes 6–18 months. Rush delivery in 2–3 business days is available for straightforward topics. Complex topics or large article sets may require additional time — we communicate any delays before they affect your deadline.
How is pricing determined?
Pricing depends on the number of articles included in the final synthesis — which you control by setting your relevance cutoff. An initial scoping fee covers PICO development, database queries, full article retrieval, and the ranked article list with a cost estimate. The full review fee is calculated per included article. You receive the final cost estimate before approving the article list, so there are no surprises.
When do I pay?
The initial scoping fee is due at order confirmation. The balance for the full review is due after you have seen and approved the ranked article list — so you know exactly what you are paying for before committing to the full synthesis.
After Delivery
What do I still need to do after receiving the document?
Three tasks remain: Review the document and submit any revision requests within 14 days. Complete the structured risk of bias table — we provide per-article signals (randomization, allocation concealment, blinding, missing data, and selective reporting) as your starting point; the judgment-based ratings require your clinical expertise. Add your own clinical interpretation in sections where journals expect author voice.
Can I request revisions?
Yes. Submit revision requests within 14 days of delivery.
Does EvidenceLab perform statistical meta-analysis?
We produce narrative synthesis only — aggregating and interpreting findings across studies in text form, without calculating pooled effect sizes or statistical heterogeneity. If your target journal requires a statistical meta-analysis (forest plots, I² statistics, pooled odds ratios), that analysis must be performed by you or a biostatistician. We provide the structured data extraction — effect magnitude language, sample sizes, study designs, follow-up durations — that makes that analysis straightforward to run.
Do you follow Cochrane methodology?
Our search and reporting standards align with PRISMA 2020. For reviews requiring strict Cochrane registration and PROSPERO protocol pre-registration, contact us to discuss requirements. Cochrane-compliant reviews involve specific registration and protocol steps that we can advise on before scope confirmation.
Ready to place an order?
Describe your research question and we will get back to you within one business day.