Ethics committees and funders increasingly expect a proper power analysis, not a guess. We prepare a written sample-size and power justification tailored to your study design that a committee will accept.
Fixed price
£180
Typical turnaround: 2–4 working days
Delivered by email · free revisions
Delivered by email · free revisions
What you get
- Sample size calculated for your specific design and outcome
- Power analysis with clearly stated assumptions
- A written justification formatted for your ethics or grant application
- Guidance on recruitment targets allowing for dropout
- A short methods paragraph you can paste straight into your protocol
How it works
Send it over
Tell us your design, your outcome measure and the effect size you expect (we can help you choose one).
We do the work
A statistician runs the power analysis and documents every assumption.
You receive it
You receive a committee-ready justification and a methods paragraph by email.
Ready to start?
Send us your data and questions and we’ll confirm a fixed price, usually within one working day. No calls.
Frequently asked questions
I don’t know what effect size to use.
That is common, and we help. We can base it on published studies in your field, a pilot, or a minimally important difference — and we document the reasoning so your committee can see it.
Will this be accepted by my ethics committee?
We write it in the format committees expect, with transparent assumptions. That is exactly what reviewers look for. Try the free power calculator first to sanity-check your numbers.
Can you also analyse the data once I collect it?
Yes — many clients come back for the analysis stage. See our statistical analysis service.