Nursing sample size and power analysis support provides a focused review of the assumptions, calculation and reporting behind a participant target. It is for students who need project-specific feedback or a reproducible planning calculation within their university’s rules.
For an independent learning walkthrough, read how to calculate sample size for a nursing dissertation. This service page explains the scope, information required and deliverables.
Choose the calculation request
- Before recruitment: review a proposed sample-size calculation and its assumptions.
- Fixed recruitment capacity: explore what the available sample can support using an appropriate sensitivity or precision approach.
- Supervisor feedback: investigate a specific criticism of your participant-target justification.
- Reporting review: check whether your own methods paragraph records the inputs and calculation transparently.
What to send with your enquiry
Include your primary question, proposed design, primary outcome, planned comparison or model, and the source of any effect-size or variability estimate. Send your current calculation, software output, recruitment limit and relevant supervisor comments where available.
If you have not chosen a primary outcome or design, identify those open decisions first through quantitative study-design support. A calculator cannot resolve an undefined research plan.
What the agreed work can include
A calculation review can return an assumptions checklist, comments on the suitability of the proposed approach, reproducible input settings and a written explanation of the result. Where appropriate, alternative assumption scenarios can show how the target changes. The agreed output should distinguish the number required for analysis from the number to approach or recruit.
A reporting review can annotate your draft justification and identify missing information. Any suggested wording must describe the work actually performed, including whether the calculation was prospective or completed after recruitment.
How we scope the task
- Confirm the question, outcome and intended analysis.
- Identify which assumptions have evidence and which remain uncertain.
- Agree the calculation approach and software, if applicable.
- Review the result against recruitment capacity and design constraints.
- Return the calculation record, limitations and agreed feedback.
When a different scope is needed
Clustered recruitment, repeated measurements, complex models or precision-based estimation may require a different approach from a simple two-group power calculation. Describe these features at enquiry stage so the request can be assessed before a calculation is promised.
If recruitment has finished, provide the original plan and actual sample. The review must not retrospectively present a new calculation as though it determined recruitment.
Frequently asked questions
Can you check a calculation I already completed?
Yes. Send the input settings, output and justification for the assumptions, together with the research plan.
Does this include analysing my collected data?
No. Existing-dataset analysis is scoped through SPSS data analysis and results support.
Can you guarantee approval of the sample size?
No. Your supervisor, institution and applicable review process retain responsibility for approval.
Request a sample-size calculation review
Send your calculation question and supporting assumptions. Include your deadline and explain whether recruitment is planned, underway or complete.