t Tests and ANOVA in Clinical Practice: DQ planning guide
Find a nursing research article that used a t test or ANOVA and judge what the statistic did for it. The prompt's fourth question offers 'weakened' as an answer, and taking that option seriously is what separates an appraisal from a summary.
Editorial process
Last reviewed · August 5, 2026
Appraising a statistic, not explaining one
You are not being asked to run a t test or an ANOVA, and you are not being asked to explain what they are. You are being asked to appraise somebody else's use of one. That distinction decides the post. A response that opens with a paragraph defining inferential statistics has spent its opening on material the prompt already supplied in its own preamble, and the four numbered headings — topic, summary, purpose and value, strengthened-or-weakened — leave no room for a tutorial. The article you pick is the object of study; the statistic is the lens you examine it through. A useful test of your draft: delete every sentence that would still be true if you had chosen a different article. Whatever survives is the appraisal, and the prompt is marking that. Everything else is preamble the marker has already read.
Choosing the article is therefore the most consequential decision, and it is made before you write a word. It has to be a primary research report — not a review, not a quality-improvement write-up — and it has to state its inferential test explicitly. The prompt gives you the selection rule in its own preamble: two groups means a t test, three or more means ANOVA. A paper comparing an intervention arm with a control arm should be reporting a t test; a paper comparing three dosing schedules or four units should be reporting ANOVA. If you cannot find the test named in the methods or under a table, pick a different paper rather than inferring which one was used. One more filter is worth applying early: the brief limits you to three references from the list in the instructions area, so an article you cannot reach through those resources costs you the citation you need.
Question 4 is where the marks separate, because it offers weakened as a live answer and most posts never take it seriously. A study can run its test perfectly and still apply weakly to practice:
What you find in the article | Why it weakens the application | What to write instead of “the results were significant” |
|---|---|---|
A p value and nothing else | Statistical significance says the difference is unlikely to be chance; it says nothing about how big the difference is | Name the missing effect size — Cohen's d for a t test, eta-squared for an ANOVA — and say what its absence prevents you concluding |
A very large sample | With enough participants a clinically trivial difference becomes statistically significant | Report the actual magnitude alongside the p value and judge whether it would change a nursing decision |
A significant ANOVA with no post-hoc test | The omnibus F says a difference exists somewhere among the groups; it does not say which groups differ | State that the pairwise comparison is missing, so the paper cannot support a claim about any specific pair |
Assumptions not addressed | ANOVA assumes independent random samples, normality and roughly equal variances | Say which assumption is unexamined and whether the design makes it plausible anyway |
The evaluation in question 3 is about the study's value to your chosen topic, not about the statistics again. This is where a reporting checklist earns its keep: most nursing articles that use a t test or ANOVA are observational, and STROBE names what an observational report ought to contain — how participants were selected, how variables were measured, how missing data were handled. Judging the paper against a published standard is a stronger move than asserting it was well conducted, and it gives you something concrete to say about sample and data sources in question 2. It also gives question 3 a shape it otherwise lacks — 'purpose and value' is an invitation to waffle until you attach it to something checkable, and a reporting checklist is the cheapest thing to attach it to. Say which items the paper satisfies and which it passes over.
Two mechanical requirements are easy to lose. The brief prescribes level-one headings numbered as in the instructions, so the four questions become four headings rather than four paragraphs of continuous prose — structure is being marked, not just content. And it asks for a minimum of 550 words with at least three references, with a complete APA citation of your chosen article included in the summary. Cite the article you appraised in full; a post that discusses a study without a retrievable citation cannot be checked by the reader it is written for. Word count is a floor rather than a target here, and 550 words across four headings is roughly 140 each, which is about one substantial paragraph per question — worth knowing before you spend three hundred of them on the summary.
Likely learning objectives
Inferred from the brief — check these against your own rubric.
- 01Select a primary research article whose inferential test is explicitly reported.
- 02Explain why the number of groups compared determines whether a t test or an ANOVA is appropriate.
- 03Distinguish statistical significance from clinical importance using effect size.
- 04Appraise an observational study against a published reporting standard rather than by impression.
- 05Judge whether an inferential statistic strengthened or weakened a study's application to practice, and defend either verdict.
Read the full question
Review every instruction before using the planning guidance that follows.
The 550 words, three references and four headings
- 01Minimum 550 words, APA format.
- 02Minimum 3 references, from the list in the instructions area.
- 03Four numbered level-one headings matching the four prompt questions.
- 04The topic identified in the first line of the posting.
- 05A complete APA citation of the selected research article, inside the summary.
- 06Sample, data sources, inferential statistic and findings, all named in the summary.
Working through the four numbered questions
1) Identify the topic, in the first line
Name the practice issue you selected before any other sentence, as the brief instructs.
2) Summarise the study, with the citation inside it
Give sample, data sources, the inferential statistic used, and the findings, with a complete APA citation of the article.
Say why this test, for this design
Connect the number of groups compared to the test reported — two groups to a t test, three or more to ANOVA — and note whether the paper's choice fits.
3) Evaluate purpose and value against a standard
Judge the study's contribution to your topic, using an explicit yardstick such as STROBE's expectations for reporting participants, variables and missing data.
4) Strengthened or weakened — commit to one
Answer the question directly, citing effect size, sample size, post-hoc testing or unexamined assumptions as the reason.
Close on what a nurse could do with it
One or two sentences on whether the finding is actionable in practice, given what the statistic did and did not establish.
How do you find an article that names its test?
Recommended databases
- CINAHL
- PubMed / PMC
- Journal of Graduate Medical Education
- EQUATOR Network
Search sequence
- 1.Search CINAHL or PubMed for your topic combined with 'analysis of variance' or 't-test' and filter to primary research; the test must appear in the abstract or methods, not be inferred.
- 2.Confirm the number of groups compared before accepting the article — this is the fastest check that the reported test was the right one.
- 3.Look up effect size reporting so question 4 can be answered with a criterion rather than an impression.
- 4.Check the article against STROBE if it is observational, and note any reporting element that is missing.
- 5.Confirm which three references your instructions area permits; the brief restricts you to that list.
Reference shortlist
These are authoritative starting points, not a ready-made bibliography. A qualified reviewer must confirm that each source fits the assignment and supports the claim beside which it is cited.
Nothing here is cleared for citation until you have read it.
- 01
Using Effect Size—or Why the P Value Is Not Enough
Journal of Graduate Medical Education (via PubMed Central) · 2012
The argument question 4 needs: significance and magnitude are different claims, and with a large sample a trivial difference becomes significant. Its aspirin example (p < .00001 with r-squared of .001) is a ready-made illustration.
- 02
13.1 One-Way ANOVA
OpenStax, Introductory Statistics 2e · 2023
The five assumptions behind ANOVA — normality, independent random sampling, equal variances, a categorical independent variable, a numerical dependent variable — which give you a checklist for judging whether the paper's test was appropriate.
- 03
10.1 Two Population Means with Unknown Standard Deviations
OpenStax, Introductory Statistics 2e · 2023
The conditions for the two-sample t test, including why variances should not be pooled when the population standard deviations may differ — the counterpart check if your article compares two groups.
- 04
The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement: guidelines for reporting observational studies
EQUATOR Network · 2007
A published yardstick for question 3. Most nursing articles using these tests are observational, and STROBE names what should have been reported about participants, variables and missing data.
- 05
Impact of prematurity and co-morbidities on feeding milestones in neonates: a retrospective study
Journal of Perinatology (via PubMed) · 2010
The worked example named in this course's own required readings: a retrospective study of 186 infants that applies inferential statistics to comorbidity effects, useful as a model of what a suitable article looks like.
Before you post: did you consider 'weakened'?
Common mistakes
- Writing a tutorial on inferential statistics. The prompt's own preamble already defines t tests and ANOVA; repeating it consumes the word budget and answers nothing.
- Answering question 4 with 'strengthened' by default. 'Weakened' is offered, and a study with no effect size, or a significant ANOVA with no post-hoc comparison, genuinely applies weakly to practice.
- Choosing an article that does not name its test. Inferring that a t test was 'probably' used makes every subsequent claim unverifiable.
- Treating a small p value as evidence of a large effect. With a big enough sample a clinically meaningless difference reaches significance.
- Reading a significant omnibus F as evidence that specific groups differ. Without a post-hoc test the paper has not identified any pair.
- Running the four questions together as continuous prose when numbered level-one headings are prescribed.
- Summarising the article's conclusions instead of its methods. Questions 2 and 3 ask for sample, data sources and statistic — the parts most summaries skip.
Submission checklist
- Topic stated in the first line, before anything else.
- Article is primary research and names its inferential test in the methods or a table.
- The test matches the number of groups compared.
- Complete APA citation of the article appears inside the summary.
- Sample, data sources, statistic and findings each explicitly identified.
- Question 4 answered with a verdict and a reason, not a restatement of the findings.
- Effect size addressed — present and interpreted, or named as absent.
- Four numbered level-one headings present.
- At least 550 words and at least three references.
Use this guide to plan and review your own work. Follow your institution's rules and read our academic-integrity policy.

Written by
Aaron Bishop
MA, Education
assignment interpretation and research-methods coaching across disciplines
Aaron leads the EssayCrackers editorial desk. He works on how assignment briefs are read — what a rubric is actually asking for, and where students most often answer a different question than the one set.

Reviewed by
Dr. Nathan Cole
PhD, Rhetoric & Composition
Argumentation and thesis development
Nathan teaches first-year composition and directs a university writing center. He reviews EssayCrackers guides for argumentative soundness and citation accuracy.