How to Compare Your Findings With Previous Studies + Phrases
By Jessica McLaren 10 min read
To compare your findings with previous studies, take each main finding in turn, cite the most relevant earlier studies on the same question, and say plainly whether your result agrees with them, partly agrees or contradicts them. Then explain any difference by population, setting, method or measure, and if you cannot find a reason, say so.
Comparing your findings with previous studies is the part of a discussion section where you place each of your results next to the published results on the same question, state how they relate, and give the most plausible reason for any difference. The comparison tells the reader what your study adds to what was already known.
| Guideline or source | What it asks the discussion to do | Applies to |
|---|---|---|
| Docherty and Smith, BMJ (1999) | Discuss “strengths and weaknesses in relation to other studies, discussing particularly any differences in results” (point 3 of a 5-part structure) | Medical and health papers |
| APA JARS-Quant, Table 1 (2024) | “Discuss similarities and differences between reported results and work of others” | Quantitative psychology and social science |
| APA JARS-Qual, Table 1 | “Identify similarities and differences from prior theories and research findings” | Qualitative research |
| STROBE checklist, item 20 | Interpret results considering “results from similar studies, and other relevant evidence” | Observational studies |
| CONSORT 2025 checklist, item 29 of 30 | “Interpretation consistent with results, balancing benefits and harms, and considering other relevant evidence” | Randomised trials |
| Ghasemi et al., Int J Endocrinol Metab (2019) | The number of references in the discussion “ranges between 10 - 20” | Biomedical papers |
Where does the comparison with previous studies go in a discussion section?
In the discussion structure Docherty and Smith proposed in the BMJ in 1999, the comparison with previous studies comes third: after the statement of principal findings and the study’s own strengths and weaknesses, and before the meaning and implications.
The BMJ structure has five parts:
- Statement of principal findings
- Strengths and weaknesses of the study
- Strengths and weaknesses in relation to other studies, discussing particularly any differences in results
- Meaning of the study: possible mechanisms and implications for clinicians or policymakers
- Unanswered questions and future research
You do not have to keep the comparison in one block. The University of Guelph’s Writing in the Sciences guide notes that “interpretations and comparisons to other studies are often integrated”: you discuss the meaning of one result, compare it to the literature, then move to the next. In a thesis chapter with several research questions, try one subsection per finding, with the comparison inside each.
What do reporting guidelines say about comparing results with other studies?
The main reporting guidelines for quantitative, qualitative, observational and trial research all ask the discussion to relate the results to earlier work, so the comparison is an expectation, not a stylistic choice. APA JARS-Quant asks you to “Discuss similarities and differences between reported results and work of others”, and APA JARS-Qual asks you to say whether findings are “challenging, elaborating on, and supporting prior research or theory”.
In health research, STROBE item 20 asks for “a cautious overall interpretation” that considers “results from similar studies”, and item 29 of the 30-item CONSORT 2025 statement (Hopewell et al., BMJ 2025;389:e081123) asks trials to consider “other relevant evidence”. Where these sources differ in emphasis, follow the guideline for your study design, or the one your supervisor or target journal names.
How do you compare your findings with previous studies, step by step?
You compare your findings with previous studies by working one finding at a time, through the same six steps.
- List your main findings. One sentence each, using only what your results section reports.
- Pick the comparison studies for each finding. Go back to your literature review and choose the studies that asked the same question. Prefer the most relevant and best-quality ones; Ghasemi et al. call comparison with low-quality or predatory journals “contextually meaningless”.
- Line up what each study did. For each one, note the population, setting, design, measure and result. A literature review matrix works well for this.
- Label the relationship. Agrees, partly agrees, contradicts, or no comparable study. Agreement needs a brief statement; a contradiction needs an explanation.
- Explain the differences. Check the matrix for a difference in sample, setting, method or measure that could account for the result.
- Say what it means. Close each comparison with what your result adds: it confirms, extends, narrows or challenges what was known.
Steal this check: can a reader tell, from your paragraph alone, which studies you agree with and why the others differ? If not, keep going.
What should you write when your findings agree, partly agree or contradict previous studies?
What you write depends on the relationship: agreement needs one or two sentences, partial agreement needs the condition under which the results match, and a contradiction needs an explanation. A missing comparison needs an honest statement and a check that you searched widely enough.
| Relationship | What to write | What to check first |
|---|---|---|
| Agrees | State it briefly and cite the studies | Whether the studies share a design or bias with yours |
| Partly agrees | Say where results match and where they diverge | Which population, setting or measure separates the two |
| Contradicts | Report the difference, then the most plausible reasons | Sample, measures, test sensitivity, design, bias |
| No comparable study | Say no directly comparable study was found | Whether your search covered other databases and languages |
How do you write it when your findings agree with previous studies?
When your findings agree with previous studies, say so briefly and cite them; Ghasemi et al. (2019) advise that consistent results be stated “briefly and simply”. One or two sentences per finding will do.
Do not treat agreement as proof. Ghasemi et al. point out that agreement “may only be due to shared biases”, so check whether the studies you cite used the same design or measure as yours; agreement across different designs is stronger evidence.
How do you explain findings that contradict previous studies?
When your findings contradict previous studies, report the contradiction directly and then give the most plausible explanations, drawn from real differences between the studies. A different result “does not necessarily indicate that there is a mistake or error”, according to Ghasemi et al. (2019).
Ghasemi et al. list differences in the sensitivity or specificity of the tests used, differences in populations, and different effects of bias. Add setting, time period or outcome definition if your matrix shows a difference there. Docherty and Smith (1999) put it simply: “discuss why you might have reached different conclusions from others”, without speculating beyond the evidence.
If you cannot find a reason, do not invent one. Ghasemi et al. are explicit: “If there is no reason for differences in findings, it should be clearly acknowledged.” Saying “the reason for this difference is unclear and would need a study designed to test it” is honest and gives you a future research point.
What if no previous study is directly comparable to yours?
If no previous study is directly comparable, say that you found none and name the nearest studies you did find, with how they differ from yours. Avoid claiming your study is the first; Ghasemi et al. (2019) warn that statements such as “for the first time” may “inflate the actual worth of the results”.
Before you write “no previous study”, check that your search was wide enough. Ghasemi et al. note: “It is always possible that the finding has been reported in a language other than English.” Run your search again in a second database, and try citation chaining from the closest paper you have.
What phrases can you use to compare your results with other studies?
Use phrases that name the relationship (consistent with, partly consistent with, in contrast to) and then the reason. Ghasemi et al. (2019) recommend the present tense when the subject is “study” or “results”, and the present perfect or past tense when the subject is “we”.
Steal these, and fill in your own studies. The authors and years below are placeholders, not real studies:
- Agrees: “This finding is consistent with (Author, Year) and (Author, Year), who reported the same pattern in [population].”
- Partly agrees: “The direction of the effect matches (Author, Year), but the association here is weaker, possibly because [difference in sample or measure].”
- Contradicts: “In contrast to (Author, Year), this study found no association between [X] and [Y]. One explanation is that (Author, Year) measured [Y] by [method], whereas this study used [method].”
- Extends: “Earlier studies examined [population A] (Author, Year); the present results suggest the pattern also holds for [population B].”
- Unexplained: “The reason for the difference from (Author, Year) is not clear from the available evidence.”
How many studies should you cite when comparing your findings?
Ghasemi et al. (2019) give 10 to 20 references as the usual range for a journal article’s discussion section, and advise discussing the most relevant studies rather than every paper in the field. That figure is for journal articles. A thesis or dissertation chapter that covers several findings is not bound by it, but the same rule holds: cite the studies that asked your question, not every study you read.
Your department’s guidance overrides any general figure; for the discussion’s own length, see how to write a discussion section.
Is comparing findings in a thesis discussion different from a journal article?
Comparing findings in a thesis or dissertation discussion follows the same logic as in a journal article, but the comparison points back to your own literature review chapter. The University of Westminster’s dissertation guide (UK) describes the discussion as interpreting findings by “comparing and contrasting them with the literature” from your literature review.
A practical test: the studies you compare against in the discussion should already appear in your literature review. If a key comparison study is new, add it to the review too. The comparison step is the same whether your institution calls the document a thesis or a dissertation.
What mistakes do students make when comparing findings with the literature?
A common mistake when comparing findings with the literature is leaving out the studies that disagree with you. Ghasemi et al. (2019) list ignoring contradictory literature, distorting it to fit your results, and avoiding unexpected results among the common pitfalls of a discussion.
The same paper also warns against summarising the literature again instead of relating it to your results, repeating results in detail, and stressing how unique your study is. The fix is a comparison matrix with the population, setting, design, measure and result of each study: if each comparison sentence traces to one row, you are comparing, not summarising.
How do I compare my findings with previous studies using an AI assistant for writing backed by sources?
You compare your findings with previous studies in Litrevu by adding the studies from your literature review, asking all of them the same questions about your variables, and lining up the answers in a cited comparison table. You then decide what agrees, what contradicts and why.
Litrevu is an AI assistant for writing backed by sources. It reads every paper, report and PDF you add, answers your questions with a citation to the exact passage behind each claim, compares sources side by side, and checks your own draft against them.
- Add the papers you will compare against. Upload PDFs, or paste a PDF link, DOI or arXiv link. Litrevu can also find open-access papers on your topic for you to choose from.
- Ask every paper the same questions. For example: “What population and setting did each study use?” and “What did each study find about [X] and [Y]?” Answers cite only your papers, and Litrevu says when your papers do not cover a question.
- Compare the papers side by side. Litrevu places the studies in a table with citations, showing where they agree and where they differ.
- Open the citations. Each one opens the highlighted passage in the source PDF, so you check the result and method yourself.
- Check your own paragraph. Paste a discussion paragraph you wrote, and each claim comes back as Supported, Partly supported, Contradicted or Not in your papers.
“Not in your papers” means your library does not cover that claim: a cue to search wider, not proof that no previous study exists. The shape of a comparison row, as a format illustration only:
| Study | Population and setting | Measure | Finding on [X] | Relation to your result |
|---|---|---|---|---|
| (Author, Year) | [as reported, cited] | [as reported, cited] | [as reported, cited] | You decide |
You make the judgement and write the discussion. Many universities do not allow AI-written text in submitted work, so check your institution’s policy and declare how you used AI.
Where can you line up your own papers against your results for free?
You can add the studies from your literature review to Litrevu and compare them side by side on your dashboard, with every answer cited to the passage in your own papers. Add your papers and compare them. Free to start, no credit card required.
Frequently asked questions about comparing findings with previous studies
How do you compare results with other studies in a discussion?
Take one finding at a time, cite the most relevant earlier studies on the same question, and say whether your result agrees, partly agrees or contradicts them. Then explain any difference by population, setting, method or measure. If there is no clear reason for a difference, say so.
What do you write if your results are consistent with previous studies?
State the agreement in one or two sentences and cite the studies, for example "This finding is consistent with (Author, Year)." Ghasemi et al. (2019) advise stating consistent results briefly and simply. Check whether the studies share a design or measure with yours, because Ghasemi et al. note that agreement may only be due to shared biases.
What if my findings contradict previous research?
Report the contradiction directly, then give the most plausible explanations from real differences between the studies, such as population, test sensitivity or bias. Ghasemi et al. (2019) note that a different result does not necessarily indicate a mistake or error. If you cannot find a reason, acknowledge that clearly rather than speculating.
How many references should a discussion section have?
Ghasemi et al. (2019) give 10 to 20 references as the usual range for a journal article's discussion section. That figure is for journal articles, not thesis chapters, and your department's guidance takes priority over any general figure. Cite the studies that asked your question rather than every paper you read.
Should the studies in my discussion be in my literature review?
Yes, in a thesis or dissertation the studies you compare against should normally already appear in your literature review chapter. The University of Westminster's dissertation guide describes the discussion as comparing and contrasting findings with the literature from your review. If a key comparison study is new, add it to the review as well.