Make a literature review matrix from your own PDFs
A literature review matrix is a table with one row per study and one column per question you ask of every study: its aim, design, sample, findings and limitations, for example. Add up to 3 of your own PDFs to fill the cells with the matching sentence from each paper, or download the blank template.
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Free literature review matrix template (Excel, Word and CSV)
Download the template and fill in one row per study as you read. No email, no sign-up. Add or delete columns to suit your question.
Excel (.xlsx) · Word (.docx) · CSV for Google Sheets · Filled-in example (Excel)
| Column | What to record |
|---|---|
| Citation (Author, Year) | Who wrote it and when, so you can cite it without looking it up again. |
| Aim or research question | What the study set out to find, in one line. |
| Design and method | How it was done, such as a trial, survey, interviews, case study or review. |
| Sample and setting | Who or what was studied, how many, and where. |
| Key findings | The results that bear on your question, in your own words. |
| Limitations | What the authors say limits their results, and anything you noticed. |
| Evidence (quote and page or section) | The sentence each note rests on, so you can check and cite it later. |
| Theme | The theme of your review this study speaks to. |
| Notes and relevance | How the study helps, or complicates, your argument. |
The first columns follow the Matrix Method, which starts every matrix with the authors, title and journal, the year, and the study's purpose (Brandeis University Writing Program handout, adapted from David Nolfi, Duquesne University, 2020; read 4 October 2026).
In Google Sheets, open the CSV with File, then Import. Freeze the first column so each study stays in view as you scroll.
What is a literature review matrix?
A literature review matrix is a table for organising your reading: one row per study, one column per question you ask of every study. Filled in as you read, it makes studies comparable, and reading down a column shows where they agree, where they disagree and what nobody has studied.
It goes by several names: literature matrix, review matrix, synthesis matrix, RRL matrix or evidence table. Health sciences teach it as the Matrix Method, from Judith Garrard's Health Sciences Literature Review Made Easy: The Matrix Method (2020), which university libraries such as VCU's teach from. Some courses set it as an assignment: San José State University's INFO 200 tells students “You must use this template for the assignment.”
| Study | Design | Sample | Key finding |
|---|---|---|---|
| Dunster et al., 2018 | Pre/post comparison: sleep measured with wrist activity devices in spring 2016 and spring 2017. | Sophomores at two Seattle public high schools; a different group of students each year. | Median school-day sleep up 34 minutes; grades 4.5% higher, though the authors find causality much harder to attribute. |
| Biller et al., 2022 | Linear mixed regression models predicting quarterly grades, using sleep data collected earlier. | 63 to 157 secondary school students aged 14 to 21, choosing an 8 AM or 8:50 AM start each day. | No systematic relationship between the flexible system and grades. |
| James et al., 2023 | Difference-in-differences, 1 year before and 2 years after the policy change. | 2,153 high school students in the START/LEARN cohort, mean age 15 at baseline. | Three fewer late arrivals; one fewer absence and GPA 0.07 to 0.17 higher, both only in the second year. |
Literature matrix, synthesis matrix, extraction table or annotated bibliography?
The names are used loosely, and many guides use them for the same table. Where they differ:
| Kind | Rows | Columns | Use it to |
|---|---|---|---|
| Literature review matrix | One per study | Questions you ask of every study | Compare studies while you read. |
| Synthesis matrix | One per study, or one per theme | Your themes or concepts, with what each source says about them (Toronto Metropolitan University's example matrix uses Concept 1 to 3 plus Gaps) | Plan the sections of your review. |
| Concept matrix | One per study | Concepts, marked when a study covers them (Webster and Watson, 2002) | See which concepts each study addresses. |
| Data extraction table | One per study | Items fixed in a protocol before you start | Systematic and scoping reviews. See how to extract and chart data. |
| Annotated bibliography | One entry per source | None: a paragraph per source | Summarise and evaluate sources one at a time. See how to write an annotated bibliography. |
Many students keep two: a matrix of studies while reading, then a synthesis matrix of themes before writing. How to synthesise sources in a literature review walks through the second.
How to make a literature review matrix in six steps
- Write your review question at the top. Every column should help answer it. Leave out a column for anything your question already fixes: if every study is about adolescents, an age column tells you nothing, as the Brandeis Matrix Method handout points out.
- Pick five to eight columns. Start with the citation, the year and the study's purpose, as the Matrix Method does, then add the design, sample, findings and limitations, or the column set for your discipline below.
- Give each study one row, and keep the full reference with it so your reference list is ready when you write.
- Fill each cell while you read, in a few words of your own. Write ‘not reported’ rather than leaving a blank, so you know later that you looked.
- Record where each note came from: a short quote, with its page or section, in an Evidence column. You will need it to cite the point and to check it.
- Read down each column, not across. Mark where studies agree, where they split and what nobody measured: those marks become your themes and your research gap. Then structure the review by theme.
Literature review matrix columns by discipline
General
Works for most empirical studies. Starts from the Matrix Method's columns.
| Column | What to record |
|---|---|
| Aim | What the study set out to find, or its research question. |
| Design | The kind of study, such as a trial, cohort, survey, interviews, case study or review. |
| Sample and setting | Who or what was studied, how many, and where. |
| Findings | The results that bear on your question. |
| Limitations | What the authors say limits their results. |
Source: Brandeis University Writing Program, The Matrix Method for Literature Reviews (adapted from David Nolfi, Duquesne University, 2020); read 4 October 2026.
Health and nursing (PICO)
For clinical and health questions framed as population, intervention, comparison and outcome.
| Column | What to record |
|---|---|
| Population | Who was studied: condition, age, setting and number. |
| Intervention or exposure | The treatment, programme or exposure studied. |
| Comparison | What it was compared with, such as placebo, usual care or another group. |
| Outcomes | What was measured, and what changed. |
| Design | Trial, cohort, case-control, cross-sectional or review. |
| Limitations | Bias, confounding, follow-up and sample size. |
Source: Richardson, Wilson, Nishikawa and Hayward (1995), The well-built clinical question: a key to evidence-based decisions, ACP Journal Club 123(3):A12; read 4 October 2026.
Quantitative
For surveys, cohorts and experiments. The items follow what the STROBE statement asks observational studies to report.
| Column | What to record |
|---|---|
| Aim | The question or hypotheses tested. |
| Design | Experiment, cohort, cross-sectional or longitudinal. |
| Sample | Size, who, how they were recruited, and where. |
| Measures | The variables, and the instruments or scales used. |
| Main finding | Direction and size of the main effects. |
| Limitations | Bias, confounding and generalisability. |
Source: von Elm et al. (2007), The STROBE statement, PLoS Medicine 4(10):e296; read 4 October 2026.
Qualitative
For interview, focus group and ethnographic studies. The areas follow the COREQ reporting checklist.
| Column | What to record |
|---|---|
| Aim | What the study set out to understand. |
| Methodology | Phenomenology, grounded theory, ethnography and the like, and any theoretical framework. |
| Participants and setting | Who took part, how they were chosen, and where. |
| Data collection and analysis | Interviews or focus groups, and how they were coded and analysed. |
| Key themes | The themes the authors report. |
| Limitations and reflexivity | Limits, and the researchers' position and its influence. |
Source: Tong, Sainsbury and Craig (2007), COREQ, International Journal for Quality in Health Care 19(6):349-357; read 4 October 2026.
Education
For studies of teaching, learning and school policy. Litrevu's suggestion: no reporting standard sets these.
| Column | What to record |
|---|---|
| Aim | What the study set out to find. |
| Setting and level | School, college or university, the level or grade, and the country. |
| Intervention or approach | The teaching approach, programme or policy studied. |
| Design | Experiment, quasi-experiment, survey, case study or review. |
| Outcomes | Learning outcomes, grades, attendance or other results. |
| Limitations | What limits the results. |
Humanities
For arguments rather than experiments. Litrevu's suggestion: no reporting standard sets these.
| Column | What to record |
|---|---|
| Argument | The central claim the work makes. |
| Primary sources | The archives, texts or other evidence it draws on. |
| Theoretical lens | The theory or framework it reads them through. |
| Period and context | The time, place and context it covers. |
| Contribution to the debate | What it adds to or changes in the scholarship. |
| Counterpoints | Objections, limits, or scholars it argues against. |
For a concept matrix (Webster and Watson, 2002), add your concepts as columns with Add your own, and note whether each study covers each one. A matrix in this tool holds 6 columns at a time.
Literature review matrix example: three studies on later school start times
Three published, open-access studies of what happens when secondary schools start later: Dunster et al. (2018) in Science Advances (CC BY-NC 4.0), Biller et al. (2022) in Scientific Reports (CC BY 4.0) and James et al. (2023) in the Journal of Adolescence (CC BY-NC-ND 4.0). Each cell has a short note in Litrevu's editors' words, then the sentence from the paper it rests on and the section it is in.
| Study | Aim | Design | Sample and setting | Findings | Limitations |
|---|---|---|---|---|---|
| Dunster et al., 2018Sleepmore in Seattle: Later school start times are associated with more sleep and better performance in high school students. Science Advances. | Whether a later school start improves school performance, tested in the field.
| Pre/post comparison: sleep measured with wrist activity devices in spring 2016 and spring 2017.
| Sophomores at two Seattle public high schools; a different group of students each year.
| Median school-day sleep up 34 minutes; grades 4.5% higher, though the authors find causality much harder to attribute.
| No control group.
|
| Biller et al., 2022A 4-year longitudinal study investigating the relationship between flexible school starts and grades. Scientific Reports. | Effects of a flexible start system on grades in 12 subjects over 4 years.
| Linear mixed regression models predicting quarterly grades, using sleep data collected earlier.
| 63 to 157 secondary school students aged 14 to 21, choosing an 8 AM or 8:50 AM start each day.
| No systematic relationship between the flexible system and grades.
| One Gymnasium, Germany's most academic school type; no socio-demographic data.
|
| James et al., 2023School start time delays and high school educational outcomes: Evidence from the START/LEARN study. Journal of Adolescence. | How educational outcomes changed in the 2 years after a start time delay.
| Difference-in-differences, 1 year before and 2 years after the policy change.
| 2,153 high school students in the START/LEARN cohort, mean age 15 at baseline.
| Three fewer late arrivals; one fewer absence and GPA 0.07 to 0.17 higher, both only in the second year.
| A natural experiment: schools were not randomly assigned, so confounding is possible.
|
Dunster et al., 2018
Sleepmore in Seattle: Later school start times are associated with more sleep and better performance in high school students. Science Advances.
- Aim
Whether a later school start improves school performance, tested in the field.
The link between longer sleep and better school performance has been hard to establish in field studies; whether delayed secondary school start times result in better performance also remains to be determined.
(Introduction)- Design
Pre/post comparison: sleep measured with wrist activity devices in spring 2016 and spring 2017.
This change was implemented for the 2016–2017 academic year and allowed us to conduct a pre-/post-study in which we measured sleep-wake cycles using wrist activity devices (Actiwatch Spectrum Plus, Philips Respironics) during the spring of 2016 (pre) and the spring of 2017 (post).
(Results)- Sample and setting
Sophomores at two Seattle public high schools; a different group of students each year.
The study populations included sophomores of two public high schools in Seattle. In each year, at the same time of the year, an independent sample of students taking the same science class was studied in each school.
(Results)- Findings
Median school-day sleep up 34 minutes; grades 4.5% higher, though the authors find causality much harder to attribute.
This asymmetric effect led to an overall 34-min increase in the sleep duration median during school days in 2017 (P = 0.0007, effect size = 0.353).
(Results)Although it is highly likely that increased sleep was the cause for reduced sleepiness, it is much harder to attribute causality for 4.5% higher grades on increased sleep…
(Discussion)- Limitations
No control group.
The nature of our pre-/post-study prevents us from having a control group.
(Discussion)
Biller et al., 2022
A 4-year longitudinal study investigating the relationship between flexible school starts and grades. Scientific Reports.
- Aim
Effects of a flexible start system on grades in 12 subjects over 4 years.
In the present study, we analysed students’ quarterly grades from 12 academic school subjects across 4 years to examine effects of this new system on academic grades in detail.
(Introduction)- Design
Linear mixed regression models predicting quarterly grades, using sleep data collected earlier.
In addition, we also used longitudinal sleep data (duration, chronotype, social jetlag), which we had previously collected in these students to predict students’ quarterly grades by means of linear mixed regression models.
(Introduction)- Sample and setting
63 to 157 secondary school students aged 14 to 21, choosing an 8 AM or 8:50 AM start each day.
Here, we studied whether 0.5–1.5 years of exposure to a flexible school start system, with the daily choice of an 8 AM or 8:50 AM-start, allowed secondary school students (n = 63–157, 14–21 years) to improve their quarterly school grades in a 4-year longitudinal pre-post design.
(Abstract)- Findings
No systematic relationship between the flexible system and grades.
When incorporating gender, grade level (i.e. indirectly age), academic quarter, and discipline in addition to school start system in the analysis, the flexible system showed no systematic relationship with students’ grades (Fig. 2b; b = − 0.10, p = 0.815, Model 1, Supplementary Table S1), hence the flexible system was not associated with students receiving better or worse grades overall in our sample…
(Results)- Limitations
One Gymnasium, Germany's most academic school type; no socio-demographic data.
Furthermore, the school studied was a Gymnasium, which is the most academic secondary school type in Germany leading directly to higher education.
(Discussion)We also lacked socio-demographic information, which likely influence grades, such as the socioeconomic status (SES), parents’ education or ethnicity of students and their parents.
(Discussion)
James et al., 2023
School start time delays and high school educational outcomes: Evidence from the START/LEARN study. Journal of Adolescence.
- Aim
How educational outcomes changed in the 2 years after a start time delay.
Thus, we evaluated how educational outcomes changed in the 2 years following a school start time delay.
(Abstract)- Design
Difference-in-differences, 1 year before and 2 years after the policy change.
We compared patterns of late arrivals, absences, behavior referrals, and grade point average (GPA) 1 year before (baseline, 2015–2016) and 2 years after (follow-up 1, 2016–2017 and follow-up 2, 2017–2018) the policy change using a difference-in-differences analysis.
(Abstract)- Sample and setting
2,153 high school students in the START/LEARN cohort, mean age 15 at baseline.
We analyzed 2153 adolescents (51% male, 49% female; mean age 15 at baseline) from START/LEARN, a cohort study of high school students…
(Abstract)- Findings
Three fewer late arrivals; one fewer absence and GPA 0.07 to 0.17 higher, both only in the second year.
A school start time delay of 50–65 min led to three fewer late arrivals, one fewer absence, a 14% lower probability of behavior referral, and 0.07–0.17 higher GPA in policy change schools versus comparison schools. Effects were larger in the 2nd year of follow-up than in the 1st year of follow-up, and differences in absences and GPA emerged in the second year of follow-up only.
(Abstract)- Limitations
A natural experiment: schools were not randomly assigned, so confounding is possible.
Schools/districts were not randomly assigned to policy conditions by the research team, meaning that there could be confounding by other student or school characteristics.
(Conclusions)
Download this example: Excel · CSV
Reading down the columns
A paragraph written from the matrix by Litrevu's editors, as an example of the synthesis step that is yours to do.
The Seattle study measured 34 more minutes of median school-day sleep after the later start (Dunster et al., 2018), the flexible-start study reports about an hour more sleep on days with a later start (Biller et al., 2022), and START/LEARN takes the sleep benefit as its starting point (James et al., 2023). On grades they split. Seattle grades were 4.5% higher, though the authors find causality much harder to attribute (Dunster et al., 2018); START/LEARN found GPA 0.07 to 0.17 points higher than at comparison schools, only in the second year of follow-up (James et al., 2023); and the flexible-start study found no systematic relationship with grades once other factors were accounted for (Biller et al., 2022). The Design and Limitations columns suggest why they differ: a pre/post comparison with no control group, a natural experiment in which schools were not randomly assigned, and a single academic-track school. All three judge academic success by grades or GPA, which Biller et al. (2022) suggest are likely a suboptimal way to evaluate timetable changes: a gap a review could name.
Sections, not pages: the tool shows a page number only when it can read one from the PDF, and this example follows the same rule. The James et al. limitation is quoted from the authors' accepted manuscript in PubMed Central (PMC10257742); every other quote is from the published version. In-text reference numbers are left out of the quotes.
From matrix to paragraphs
Group the column notes into themes. A theme is a question two or more studies answer, such as whether later starts improve grades. See how to structure a literature review by theme.
Write one paragraph per theme that compares studies, not one per study. Open with the point, give the evidence from two or three rows, then say what you make of the agreement or the split. How to synthesise sources shows the pattern.
Cite from the Evidence column, and check each quote against the paper before you hand anything in. The Limitations column is where your appraisal goes: how to critically appraise a research paper.
How this tool fills the matrix, and its limits
- Up to 3 PDFs and 6 columns per matrix. A PDF needs selectable text: a scan without it cannot be read.
- Each PDF goes into a private Litrevu library, where it is read and split into passages.
- For each column, one search across your papers finds up to two passages in each paper that come closest to it. It is the same search the Litrevu assistant uses to compare papers.
- Each cell then quotes, word for word, the sentence in those passages that uses the most words from Litrevu's list of words papers tend to use for that column; for a column you add, the list is your own words. When no sentence uses any of them, the cell says No clear answer in the closest passage, and still shows you the passage.
- A page number appears only when Litrevu could read it from the PDF, and for most new uploads it cannot yet. You can always find the quoted sentence by searching your PDF for it.
- The tool quotes; it does not judge. The sentence it picks can miss the point or answer a different question, so open each passage and write the note yourself.
- Building a matrix is free, needs no sign-up and uses none of your free words. As a guest, this page adds PDFs to your free library until it holds 3 papers, and you can rebuild the matrix with other columns as often as you like, within an hourly limit.
Your papers and privacy
Your library is private: nobody else can see it. Data travels encrypted in transit (HTTPS). To read your PDFs, Litrevu sends their text to its AI providers, currently OpenAI and Google. Your PDF files stay in our own cloud storage and are not sent to them.
As a guest, your work may be deleted after 48 hours unless you create a free account. You can remove a paper from your library at any time; removing it does not by itself delete the stored copy of the file.
Only add papers you have the right to use for research, as Litrevu's terms ask. Some universities also restrict putting other people's work into AI tools, so check your institution's policy first. The privacy policy has the details.
Questions
What is a literature review matrix?
A table you fill in while you read: one row per study and one column per question you ask of every study, such as its aim, design, sample, findings and limitations. Because every study answers the same questions in the same place, you can read down a column to see where studies agree, where they disagree and what nobody has looked at. Health sciences teach it as the Matrix Method.
What does a literature review matrix look like?
Like a spreadsheet. The first columns identify the study: the Matrix Method starts with the authors, title and journal, the year, and the study's purpose. The rest hold short notes in your own words, ideally with a quote and its page or section beside each one. The worked example on this page shows three real studies of later school start times.
What is a literature review matrix used for?
To record the same details from every study, so you compare like with like, and to find your themes and your research gap before you start writing. It is usually a working document rather than something you hand in, though some courses set it as an assignment.
What is the difference between a literature matrix and a synthesis matrix?
The names are used loosely, and many guides use them for the same table. Where they differ, a literature or review matrix has a row per study and records what each study says. A synthesis matrix puts your themes or concepts first and records what each source says about each one; Webster and Watson (2002) call the concept version a concept matrix. Many students keep both: one while reading, one while planning the argument. The literature review is the prose you write from them.
What columns should a literature review matrix have?
Start with the citation, year and purpose, as the Matrix Method does, then add the questions your review needs answered of every study. Aim, design, sample, findings and limitations suit most empirical work, and library guides list similar headings: Liberty University's names the theoretical or conceptual framework, research questions, methodology, analysis and results, conclusions, and implications. Leave out any column your question already fixes. The column sets on this page give a starting point for health, quantitative, qualitative, education and humanities research.
What columns work for qualitative research?
Aim and research question; methodology, such as phenomenology or grounded theory, with any theoretical framework; participants and setting; how data were collected and analysed; the key themes; and limitations, including the researchers' reflexivity. These follow the areas the COREQ checklist asks qualitative studies to report (Tong, Sainsbury and Craig, 2007).
Should I make my matrix in Excel, Word or Google Sheets?
A spreadsheet is easier once you have more than a handful of studies, because you can sort, filter and freeze the first column. A Word table suits a short matrix you will print or hand in. The template on this page comes as an Excel file, a Word file and a CSV that Google Sheets, Numbers and Excel all open.
How many studies should a matrix hold?
Every study your review will discuss: the matrix grows with your reading. This tool fills 3 papers at a time. In the Litrevu workspace the assistant can compare up to 10 papers in one request, and a free library holds up to 20 papers. To estimate how many sources your word limit calls for, use the Dissertation Word Count Calculator.
Is an RRL matrix the same thing?
Yes. Where a literature review is called a review of related literature (RRL), the RRL matrix is the same table: one row per study, with columns for what you record about each. If your teacher gave you a column list, use theirs.
Can I use AI to fill in a literature review matrix?
A tool can help you find where each paper addresses a question, as this one does, but the matrix is only as good as your reading. Research on AI extraction tools agrees: a 2026 study found that the supporting quotes one such tool gave matched across two user accounts in only 46% of cases, and concluded that it “can complement, but not replace, human data extractors” (Lagisz et al., 2026). Check each cell against its passage and write the note yourself. Rules on declaring AI use differ by university: check your assessment brief, and the AI Disclosure Statement Generator gives you the declaration in your university's own format where it has one, and a general one where it does not.
Why does a cell say “No clear answer in the closest passage”?
For each column the tool takes up to two passages in that paper that come closest to it, then looks in them for the sentence that uses the most of the words papers tend to use for that column (for a column you add, your own words). When no sentence uses any of them, it says so rather than quoting something unrelated. The paper may not report it, or may put it in other words: open the passage, try a column phrased the way the paper would phrase it, or check the PDF.
Why do some cells have no page number?
A page shows only when Litrevu could read it from the PDF, and for most new uploads it cannot yet. The cell still quotes the sentence, so you can find it by searching the PDF for those words. Page numbers are never guessed.
What happens to the PDFs I upload?
They go into a private Litrevu library that nobody else can see. To read them, Litrevu sends their text to its AI providers, currently OpenAI and Google; the PDF files stay in our own cloud storage and are not sent to them. As a guest, your work may be deleted after 48 hours unless you create a free account. You can remove a paper from your library at any time; removing it does not by itself delete the stored copy of the file. The privacy policy has the details.
Is it free?
Yes. Building a matrix is free, needs no sign-up and uses none of your free words. The templates are free downloads with no email.
Can I keep working with the papers afterwards?
Yes. Keep going opens Litrevu with the papers in your library. There you can ask where the studies agree and disagree, add more papers, and press “Compare my papers on” for a short answer per cell, with citations that point to passages in your papers. A free account keeps your work past 48 hours.
Sources
- Brandeis University Writing Program, The Matrix Method for Literature Reviews, adapted from David Nolfi, Duquesne University, 2020. Quoted: “Every review matrix should have the same first three column headings: (1) authors, title, and journal, (2) publication year, and (3) purpose” and “Do not include column headings that are explicit in your research question”. https://www.brandeis.edu/writing-program/resources/faculty/handouts/matrix-method-literature-reviews.html (read 4 October 2026)
- Duquesne University Gumberg Library, Matrix Method for Literature Review: Sample Matrix and Templates. https://guides.library.duq.edu/matrix/templates (read 4 October 2026)
- VCU Libraries, How to Conduct a Literature Review (Health Sciences and Beyond): Organize Key Findings, which draws on Judith Garrard, Health Sciences Literature Review Made Easy: The Matrix Method (2020, ISBN 9781284211184). https://guides.library.vcu.edu/health-sciences-lit-review/organize (read 4 October 2026)
- Toronto Metropolitan University, Organize your Readings with a Literature Review Matrix (its example matrix has the columns Sources, Methods, Concept 1 to 3, and Gaps). https://pressbooks.library.torontomu.ca/graduatereivews2/chapter/organize-your-readings-with-a-literature-review-matrix/ (read 4 October 2026)
- Liberty University, Literature Matrix, AMA Writing Guide. https://libguides.liberty.edu/c.php?g=1166283&p=8631257 (read 4 October 2026)
- San José State University, INFO 200, Literature Review Matrix. https://infocom.hyperlib.sjsu.edu/assignments/literature-review-matrix/ (read 4 October 2026)
- Webster, J. and Watson, R. T. (2002). Analyzing the past to prepare for the future: writing a literature review. MIS Quarterly, 26(2), xiii-xxiii. https://doi.org/10.2307/4132319 (read 4 October 2026)
- Richardson, W. S., Wilson, M. C., Nishikawa, J. and Hayward, R. S. (1995). The well-built clinical question: a key to evidence-based decisions. ACP Journal Club, 123(3), A12. https://doi.org/10.7326/ACPJC-1995-123-3-A12 (read 4 October 2026)
- Tong, A., Sainsbury, P. and Craig, J. (2007). Consolidated criteria for reporting qualitative research (COREQ). International Journal for Quality in Health Care, 19(6), 349-357. https://doi.org/10.1093/intqhc/mzm042 (read 4 October 2026)
- von Elm, E. et al. (2007). The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement. PLoS Medicine, 4(10), e296. https://doi.org/10.1371/journal.pmed.0040296 (read 4 October 2026)
- Lagisz, M., Mizuno, A., Morrison, K., Pollo, P., Ricolfi, L., Yang, Y. and Nakagawa, S. (2026). Using Elicit AI research assistant for data extraction in systematic reviews: a feasibility study across environmental and life sciences. Research Synthesis Methods, 1-18 (CC BY 4.0). https://doi.org/10.1017/rsm.2026.10080 (read 4 October 2026)
- Dunster et al., 2018. Sleepmore in Seattle: Later school start times are associated with more sleep and better performance in high school students. Science Advances, 4(12), eaau6200. Quoted from the full text (PMC6291308), CC BY-NC 4.0. https://doi.org/10.1126/sciadv.aau6200 (read 4 October 2026)
- Biller et al., 2022. A 4-year longitudinal study investigating the relationship between flexible school starts and grades. Scientific Reports, 12(1), 3178. Quoted from the full text (PMC8873390), CC BY 4.0. https://doi.org/10.1038/s41598-022-06804-5 (read 4 October 2026)
- James et al., 2023. School start time delays and high school educational outcomes: Evidence from the START/LEARN study. Journal of Adolescence, 95(4), 751-763. Quoted from the Crossref abstract and author manuscript (PMC10257742), CC BY-NC-ND 4.0. https://doi.org/10.1002/jad.12151 (read 4 October 2026)
Related guides
- How to Synthesize Sources in a Literature Review (Step-by-Step, With Examples)
- How to Extract and Chart Data from Studies for a Literature Review
- How to Find a Research Gap (Step-by-Step, With Examples)
- How to Structure a Literature Review by Theme (With Examples)
- How to Critically Appraise a Research Paper (CASP Checklist, With Examples)
- How to Write an Annotated Bibliography (With Examples)
- How to Write a Literature Review (Step-by-Step Guide for 2026)
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Paste a reference list to see which references are real, which details are wrong, and which papers are retracted, checked against Crossref and OpenAlex.
- AI Disclosure Statement Generator
Pick your university and what you used AI for to get its own AI declaration filled in, a reference for the tool in APA, Harvard or MLA, and the records to keep.