Meta-analysis services for systematic reviews

From effect-size extraction to a peer-review-ready forest plot, we run the quantitative synthesis behind your review and hand you results you can defend.

4.9 / 5 across 1,194+ delivered projects

  • Cochrane and PRISMA 2020 methods
  • PhD methodologists
  • 100% human-written, no generative AI
  • Reproducible R and Stata code
  • Free quote within 24 hours
  • Mutual NDA on request

A meta-analysis statistically combines the results of the studies in a systematic review into a single pooled effect estimate, weighting each study by its precision. Our service covers the whole quantitative stage: effect-size extraction, choosing the fixed-effect or random-effects model, quantifying heterogeneity, building forest and funnel plots, testing for publication bias, and rating certainty with GRADE, all with reproducible code.

When a meta-analysis is the right choice

Pooling is only sound when the studies are similar enough to be estimating a comparable effect. We start by checking that your included studies share a clinical and methodological logic, then judge whether the heterogeneity is low enough for a pooled number to mean something. When it is not, we are direct about it and run a structured narrative synthesis instead, rather than forcing a misleading single estimate.

The choice of effect measure matters as much as the model. We pick the odds ratio, risk ratio, mean difference, or standardized mean difference that fits your outcomes and your readers, and we explain the trade-off so the analysis answers your review question rather than the other way round.

What the service covers

  1. 1

    Effect-size extraction

    We pull the effect estimate and its variance from every included study, converting between scales where studies report outcomes differently so they enter one analysis.

  2. 2

    Model selection and pooling

    We choose fixed-effect or random-effects pooling on a stated rationale, then compute the pooled estimate with a confidence interval and a clear interpretation.

  3. 3

    Heterogeneity and exploration

    We quantify heterogeneity with Cochran's Q, I-squared, and tau-squared, then explore it with subgroup analysis and meta-regression where the data allow.

  4. 4

    Bias, robustness, and certainty

    We test small-study effects with funnel plots and Egger's test, run sensitivity analyses, and rate the certainty of evidence with GRADE.

The software and methods behind your pooled estimate

The analysis is only as defensible as the tooling it runs on. We work in scripted, version-controlled environments so every number traces back to a line of code, and we match the method to your data rather than forcing your data into one default routine.

R with metafor and meta

Our primary environment for pooling, heterogeneity statistics, meta-regression, and every plot, scripted so the analysis reruns end to end.

Stata and RevMan when required

We deliver in Stata or produce RevMan output where a Cochrane review group or a target journal expects that format.

The right pooling model

Inverse-variance, Mantel-Haenszel, or Peto methods under a fixed-effect or random-effects framework, chosen on a stated rationale, not habit.

Advanced synthesis where it fits

Network meta-analysis for multiple comparators, dose-response models, and proportion meta-analysis for single-arm evidence.

What you receive

You get the pooled results, publication-quality forest plots and funnel plots, the heterogeneity and bias diagnostics, and a methods-and-results write-up aligned with the PRISMA 2020 reporting guideline. Every figure ships with the analysis script, so the work is reproducible and your reviewers can see exactly how each number was produced. If you would rather try the pooling yourself first, our free meta-analysis calculator runs both models on your own numbers.

  • Pooled effect estimate with confidence interval and a plain-language interpretation
  • Forest plot, funnel plot, and any subgroup or cumulative plots your review needs
  • Cochran's Q, I-squared, and tau-squared with a reading of what the heterogeneity means
  • Egger's test, trim-and-fill, and a small-study-effects assessment
  • Subgroup, meta-regression, and sensitivity analyses specified in your protocol
  • A methods-and-results section drafted for your manuscript, plus the annotated R script

Who commissions a meta-analysis from us

The brief differs by who is asking, and we shape the analysis and the write-up to match. Doctoral candidates need a defensible quantitative chapter and a viva they can answer for; clinicians and guideline teams need a pooled estimate that will survive editorial and peer scrutiny; and authors in revision need a specific reviewer demand answered quickly and cleanly.

Doctoral and master's researchers

A reproducible synthesis chapter you can defend, with the reasoning behind every modelling choice explained so the work is genuinely yours.

Clinicians and guideline developers

Pooled estimates and certainty ratings built to the standard a clinical guideline or a systematic review journal will expect.

Authors answering reviewers

Targeted reanalysis when a reviewer asks for a random-effects model, a sensitivity analysis, or a publication-bias test on an existing review.

Research groups without a statistician

An embedded review statistician for the quantitative stage when your team has the clinical expertise but not the modelling time.

How a meta-analysis is quoted

We quote a fixed fee per project rather than charging by the hour, so the cost is known before any work begins. What sits behind that number is the amount of analytical work your evidence actually requires: the count of included studies and outcomes, whether effect sizes need converting between scales, whether you need a single pairwise pooling or a full network meta-analysis, and how much of the methods-and-results writing you want us to draft. Send your included studies and your outcomes and we will scope the analysis and return a fixed quote, with no obligation to proceed.

Running the pooling yourself versus a review statistician

ConsiderationDoing it yourselfWorking with our statistician
Model choiceEasy to default to one model without a stated rationale reviewers will acceptFixed-effect or random-effects chosen and justified against your data
HeterogeneityOften reported as a single number with no interpretationQuantified, explored with subgroups and meta-regression, and explained
ReproducibilityPoint-and-click steps are hard to document and repeatA scripted analysis that reruns and is handed over in full
Reviewer questionsA new reviewer demand can mean relearning the method under deadlineReanalysis and a written response turned around without starting over

Frequently asked questions

What is included in a meta-analysis service?
A full meta-analysis covers effect-size extraction from each included study, choosing the right effect measure and model, pooling with fixed-effect or random-effects methods, quantifying heterogeneity, producing forest and funnel plots, testing for publication bias, running subgroup and sensitivity analyses, and rating the certainty of evidence with GRADE. You receive the results, the figures, and the code that produced them.
How many studies do you need for a meta-analysis?
A meta-analysis can technically be run on two studies, but the random-effects estimate of between-study variance is unreliable with very few studies. Many methodologists suggest caution below about five studies and interpret heterogeneity statistics conservatively. Where pooling is not appropriate, a structured narrative synthesis is the right alternative.
Which software do you use for the analysis?
We work in R (the metafor and meta packages) and can also deliver in Stata or with RevMan output where a journal or review group requires it. Every analysis ships with the script so your results are fully reproducible and can be rerun or extended.
Can you run a meta-analysis on data I have already extracted?
Yes. If you have a clean extraction table with effect estimates and their variances, or the raw counts and sample sizes, we can take it straight to analysis. We check the data first and flag anything that needs resolving before pooling.

Tell us your outcomes and your included studies, and we will recommend a plan and a fixed quote for the analysis.

Free quote within 24 hours. 100% human-written by PhD methodologists.

Methodology reviewed by

Dr Marcus Halloran, PhD

Senior Review Statistician

Runs the quantitative synthesis: pooling models, heterogeneity, network meta-analysis, and the figures that go in the paper.

Why researchers bring in a PhD methodologist

80+

systematic reviews are published every day (Hoffmann et al., 2021)

67.3 weeks

average time to complete a review in-house (Borah et al., BMJ Open 2017)

~70%

of published reviews rate critically low on AMSTAR 2 quality appraisal

4.9 / 5

our client rating across 1,194+ delivered projects