In health sciences dissertations, a literature review commonly spans 20–30% of the total word count, shaped by degree level and scope.
A clear size target saves time, cuts drift, and keeps your chapter aligned with examiners’ expectations. In the health field, the sweet spot for the review is usually a percentage of the whole project rather than a fixed page count. The exact slice depends on degree level, study design, and your program’s handbook. Below you’ll find practical ranges, a quick calculator, and ways to adapt the chapter for narrative, scoping, and systematic builds.
Recommended Literature Review Length For Health Sciences
Most programs steer students toward a proportional target. For taught degrees, the review is a compact chapter that sets up the project. For doctoral work, it becomes a broader map that positions the study in clinical or public-health evidence. The ranges below reflect common guidance across universities and typical thesis sizes in medicine and allied fields.
Typical Ranges By Degree And Project Size
| Degree Level | Typical Thesis Size | Review Share & Words |
|---|---|---|
| Undergraduate (Health-related) | 8,000–12,000 words | 15–25% → ~1,200–3,000 words |
| Master’s (e.g., MPH, MSc Nursing) | 10,000–20,000 words | 20–30% → ~2,000–6,000 words |
| Doctorate (PhD/DrPH, biomedical sciences) | 60,000–90,000 words* | 20–25% → ~12,000–22,500 words |
*Many medical faculties cap doctoral theses around ~80,000 words; always check your graduate school handbook.
Why The Percentage Target Works Best
Health topics carry dense evidence. A percentage target scales with project scope, helps you avoid bloated summaries, and leaves room for methods and results. It also lines up with common assessment rubrics that grade balance across chapters.
Map Your Chapter To Your Dissertation Type
Pick the size that matches your study design and evidence needs. Then shape the sections so each page earns its place: frame the clinical or public-health problem, define the search scope, group themes, weigh quality, and surface gaps that lead into your research questions.
Narrative Review For Applied Projects
This style suits service evaluations, feasibility studies, or small observational projects. Aim for a tight synthesis that lands on a clear gap and a workable question. Keep a short methods note for search scope and inclusion choices, then move fast to themes and critiques.
Scoping Review Within A Thesis
Use this when a field is fragmented or emerging. Expect more space than a narrative review due to broader sourcing. Chart sub-topics, map study designs, and show where the evidence thins out. A concise mapping table or figure helps the reader grasp the terrain.
Systematic Review Chapter
Some health theses build a systematic review chapter to underpin later empirical work. This needs a fuller methods note (databases, dates, criteria), a PRISMA-style flow diagram, and tables for study features and bias checks. That extra reporting inflates word count; budget near the top of the ranges.
Set Your Word Budget Step By Step
1) Confirm The Total Cap
Before you draft, confirm the thesis cap with your faculty. Medical and life-science programs often set clear totals and formatting rules. Once you have the cap, carve out a realistic allowance for the review.
2) Pick A Percentage Band
Use 20–25% for doctoral projects, 20–30% for taught master’s, and 15–25% for undergraduate work. Slide upward if you’re running a scoping or systematic review inside the thesis, or if your field has sprawling debates that need careful synthesis.
3) Cross-check With Your Supervisor
Bring a one-page outline and the target word range to a quick meeting. Agree on the section weights early (background, scope, themes, critique, gap) so you don’t end up trimming late.
Section-By-Section Word Guide
Here’s a flexible split for a health dissertation review. Adjust to fit your design and the density of prior studies.
Background & Problem Framing
Keep this brisk: set clinical or public-health stakes, define the population, setting, and outcomes of interest, and link to the aims that follow in your methods chapter.
Search Scope & Selection
Briefly state databases, date limits, language choices, and key criteria. If you’re not doing a full systematic build, a short paragraph still helps readers trust your coverage.
Thematic Synthesis
Group the field by intervention types, pathways, metrics, or settings. Write in short subsections. Where trials or cohort data converge, say so; where findings clash, propose reasons tied to design or bias.
Quality And Bias
Add a compact paragraph on common biases in the field: selection, measurement, confounding, or small-study effects. Point to frequent reporting gaps that matter for your topic.
Gap And Research Rationale
End with a clear, one-paragraph bridge into your study aims. Name the gap you’ll address and the value to practice or policy.
Trusted Guides You Can Use Mid-Draft
For practical steps on planning and writing the chapter, the Sheffield literature review guide walks through organising sources and writing a clear, critical synthesis. For health policy and applied topics, see the LSE dissertation guidelines on scope and critical evaluation. Both pages are handy checklists during drafting.
Size Tuning For Common Health Projects
Use these ranges when you need a quick target. They fit most health dissertations that include a review as one chapter, not a standalone publication.
Applied Clinical Project (Master’s)
- Target: 2,500–4,500 words.
- Why: Enough space to compare interventions or pathways and flag practice gaps.
- Tip: Add one compact table to summarise core studies by setting and outcome.
Public Health Evaluation (Master’s)
- Target: 3,000–5,000 words.
- Why: Broader contexts and policy angles stretch the synthesis a bit.
- Tip: Weave in measurement limits and equity notes where relevant.
Biomedical PhD With Empirical Chapters
- Target: 12,000–18,000 words.
- Why: Deeper mechanistic threads, multiple pathways, and prior animal or lab models push coverage.
- Tip: Split into subsections tied to mechanisms or assay families so readers can scan fast.
Second-Pass Checks That Keep Length On Track
Prune Summaries, Keep Synthesis
Cut repetitive study-by-study narration. Lead with patterns, then name a few flagship studies as anchors. This trims words while raising clarity.
Keep Methods Notes Proportionate
Reserve long search strings and extra tables for an appendix unless your program asks for full detail in-chapter.
Balance Space With Methods And Results
Don’t let the review crowd out your methods or results. If the review creeps over plan, compress background paragraphs and merge closely related themes.
Word Budget Scenarios
Pick the row that matches your total cap and you’ll have a fast, defensible range. Shift to the upper band for scoping or systematic builds inside the thesis.
Quick Calculator: From Total Words To Review Size
| Total Thesis Words | 20% Target | 30% Target |
|---|---|---|
| 8,000 | 1,600 | 2,400 |
| 12,000 | 2,400 | 3,600 |
| 15,000 | 3,000 | 4,500 |
| 20,000 | 4,000 | 6,000 |
| 80,000 | 16,000 | 24,000 |
| 90,000 | 18,000 | 27,000 |
Signals Examiners Look For
Clear Scope
State populations, settings, comparators, and core outcomes up front. Give readers the guardrails so they can judge coverage and depth.
Coherent Themes
Group studies by intervention, pathway, metric, or context instead of marching in chronological order. This structure makes the chapter easier to scan.
Critique That Leads To A Gap
Point to design limits and measurement issues that matter for your topic. Link those limits to the study you’ll run next.
When Your Review Needs More Space
Bump the allowance if you’re combining clinical trials with lab models, covering multiple demographic groups, or embedding a full systematic method. Signal the reason for the extra pages in a short preface line at the start of the chapter.
When To Tighten
- Too many single-study summaries with no synthesis.
- Repeated background paragraphs that restate the same context.
- Method notes that belong in an appendix.
Style Tips That Keep Readers Engaged
- Short paragraphs (2–4 sentences) and clear subheads.
- Plain verbs; use numbers and named measures where possible.
- Tables and small figures to compress data when a theme runs long.
Ethics, Reporting, And Transparency
Health topics draw scrutiny. Log your search windows, database names, and screening steps. If you assessed bias or certainty, state the tool and a one-line takeaway. Put the fine detail in an appendix to save words in the main chapter.
Practical Takeaway
Pick a percentage, set a word band, and draft to that target. For taught degrees, land in the 20–30% range. For doctoral work, aim for 20–25%. Raise the allowance when your chapter includes scoping or systematic elements. Clear scope, clean themes, and a sharp gap statement will do more for your grade than extra pages ever will.