The Celsus meta-analysis service is built for theses, journal articles and projects that need a systematic review protocol. We turn the scattered findings of individual studies into a transparent, reproducible evidence synthesis that meets the PRISMA 2020 standard. For researchers in the health sciences, education, psychology and the social sciences, we deliver a quantitative synthesis that is defensible under peer review and ready for journal submission.
What's included
- Framing the research question with PICO/PECO and drafting the protocol (including a PROSPERO registration draft where appropriate).
- Building the database search strategy (PubMed, Scopus, Web of Science, PsycINFO) with fully documented, reproducible search strings.
- Dual screening by two independent reviewers, conflict resolution and a Cohen's kappa agreement report.
- Data extraction from included studies and risk-of-bias assessment (RoB 2 / ROBINS-I).
- Computing and pooling effect sizes under both fixed- and random-effects models.
- Heterogeneity (I², τ², Q), publication-bias diagnostics (funnel plot, Egger's test, trim-and-fill) and sensitivity analyses.
- PRISMA flow diagram, forest plot, funnel plot and a submission-ready methods write-up, with all R/RevMan code and data.
How we work
- Scope: We discuss your research question, eligibility criteria and target journal, draft the protocol and send a scoped fixed quote within one working day.
- Preparation: We build the search strategy, run the dual screening and standardise the extraction sheet, documenting every step so it can be audited.
- Analysis: We pool effect sizes, test heterogeneity and publication bias, and run subgroup and sensitivity analyses.
- Reporting and aftercare: We deliver the PRISMA-compliant results section, the figures and the reproducible code, and support any extra analyses requested during peer review.
Meta-analysis steps and deliverables
| Step | Deliverable | Tool |
|---|---|---|
| Protocol and search strategy | PICO framework, search strings, PROSPERO draft | Rayyan, reference manager |
| Study selection | Dual-screening records, kappa agreement, PRISMA flow diagram | Rayyan |
| Data extraction and bias | Extraction sheet, RoB 2 / ROBINS-I appraisal | Excel, robvis |
| Effect-size pooling | Forest plot, pooled estimate and confidence interval | R (metafor), RevMan |
| Heterogeneity diagnostics | I², τ², Q statistic; subgroup analysis | R (metafor) |
| Publication bias | Funnel plot, Egger's test, trim-and-fill | R (metafor) |
| Reporting | PRISMA-compliant text, figures, reproducible code | R Markdown / RevMan |
The growth of meta-analysis publishing
Related guides
If you would like to understand the method in more depth, our meta-analysis and PRISMA guide is a good starting point. To decide which effect size suits your data, see our guide to effect sizes, and for how to report the results consult our APA 7 statistics reporting checklist.
Frequently Asked Questions
How long does a meta-analysis take?
It depends on the number of included studies and the breadth of the search. A narrowly scoped review can take a few weeks, while a large literature takes longer. Once the scope is clear we share a realistic timeline.
How is the price determined?
We base the price on scope factors such as eligibility criteria and analytical depth. You receive a scoped fixed quote within one working day, with no surprise charges along the way.
Is my data and draft kept safe?
All materials are kept confidential. We sign a non-disclosure agreement on request and our work is aligned with UK GDPR and KVKK. Your data is deleted on completion if you ask us to.
How do I get started?
Send your research question and eligibility criteria through the contact form or via WhatsApp. We draft the protocol and reply with a scoped fixed quote within one working day.