Decoding the Scope and Delimitations of the Study in Research

Key Takeaways:

• Scope defines what a study covers; delimitations define what a researcher deliberately excludes, and why.
• Scope and delimitations belong in 4 places in a paper: the Abstract, Introduction, Methods, and Discussion, not just one section.
• Delimitations are choices a researcher controls; limitations are constraints a researcher does not control.
• Specific, well-justified scope and delimitation statements make a study easier to evaluate, replicate, and defend.

Glossary of Key Terms

What Is the Scope of a Research Study?

The scope of a research study is the boundary that defines what the study investigates. It states the variables, population, timeframe, and setting the researcher plans to examine, and it separates what is included from everything else that is not.

A clear scope statement previews a paper’s content before a reader reaches the full methodology. It also guides the researcher’s own planning, since the scope determines what data need to be collected and which tools are required to collect them.

A scope statement typically specifies:

• The variables studied and how they are measured
• The population or sample under investigation
• The geographic, institutional, or laboratory setting
• The time period covered by the data

What Are Delimitations in a Research Study?

Delimitations are the deliberate choices a researcher makes to exclude certain variables, groups, or factors from a study, along with the reasoning behind each choice. They narrow the scope into something manageable and specific.

Every delimitation is a decision, not an accident. A researcher chooses one age group over another, one geographic region over another, or one methodology over another, and then explains why that choice best serves the research question. This reasoning is what separates a delimitation from an arbitrary gap in the study.

A Simple Example of Scope and Delimitations

Research question: What is the effect of regular physical exercise on the health of senior citizens?

• Scope: physical and mental health outcomes among senior citizens who exercise regularly
• Delimitation 1: participants aged 65 to 75 only
• Delimitation 2: one specific geographic region
• Delimitation 3: aerobic exercise only, not resistance training
• Delimitation 4: a 6-month data collection period

How Are Delimitations Different from Limitations?

Delimitations are choices a researcher makes on purpose before a study begins. Limitations are constraints the researcher did not choose and could not fully avoid, such as a small sample size or restricted access to data.

Delimitations are stated in the Introduction alongside the research aims. Limitations are typically discussed later, in the Discussion section, once the researcher can describe how those constraints actually affected the findings.

Scope vs Delimitations vs Limitations at a Glance

See also: 7 Best AI Tools for STEM Research

Where Should You Write Scope and Delimitations in a Paper?

Scope and delimitations should appear in 4 places: briefly in the Abstract, more fully in the Introduction, in full detail in the Methods section, and again in the Discussion when interpreting results.

Abstract and Introduction

State the scope in 1 or 2 sentences in the Abstract so readers immediately know what the study covers. In the Introduction, expand on this by naming the key delimitations and briefly explaining why each one was chosen.

Methods Section

The Methods section is where scope and delimitations get justified in full. Describe the population, sampling approach, variables, instruments, and timeframe in enough detail that another researcher could assess or replicate the design.

Discussion Section

Return to the scope and delimitations when interpreting results. Explain how the chosen boundaries shaped the findings, and note what the study cannot claim as a result of those boundaries. This helps readers avoid over-generalizing the conclusions.

How Do You Write Scope and Delimitations Step by Step?

Start by defining the research question, then decide what to include and exclude across 6 factors: variables, population, setting, timeframe, methodology, and data source. Justify each exclusion in 1 sentence.

Questions to Answer Before You Write

• What are the study’s aims and objectives?
• Which variables are included, and which are deliberately excluded?
• Who or what is the target population?
• What is the geographic or institutional setting?
• What is the timeframe for data collection?
• Which research design and methodology are used?
• Which data collection tools and analysis techniques are used?
• Why were competing options rejected in favor of these choices?

Useful Phrases for Writing Scope and Delimitations

Ready-made phrasing can help writers move from a blank page to a clear statement quickly. The phrases below can be adapted to most disciplines.

For scope:

• This study focuses on, considers, or investigates the following factors
• This study aims to examine the relationship between…
• The overall objective of this research is to…

For delimitations:

• This study does not address [topic], since it has been examined extensively elsewhere
• A review of [topic] lies outside the scope of this study
• The following factors were excluded from this study: …
• This study draws on selected, pertinent sources rather than an exhaustive review of [topic]

What Do Scope and Delimitations Look Like in Published Research?

Published studies typically state scope in 1 or 2 sentences in the introduction, then list delimitations as short clauses in the methods section, often tied directly to the sampling and measurement approach.

Example 1: Psychological Impact Study

Simione and Gnagnarella (2020) compared the psychological and behavioral impact of the COVID-19 pandemic on health care workers and the general population in Italy. Their scope covered specific outcomes, including anxiety and death anxiety, measured through a validated questionnaire. Their delimitations included a convenience sampling method, a defined set of demographic variables such as age and sex, and a named statistical software package for analysis.

Example 2: Postoperative Physiotherapy Study

Johnsson and colleagues (2019) examined the effect of in-hospital physiotherapy on postoperative physical capacity, activity, and lung function in patients recovering from lung cancer surgery. Their scope was narrowed through delimitations covering a specific surgical procedure, a defined hospital setting, and a fixed postoperative measurement period, which together made the study’s boundaries explicit to readers.

Rewriting a Vague Scope Statement

A common early draft problem is a scope statement that sounds specific but is not. Comparing a vague version with a revised version shows what precision looks like in practice.

Do Scope and Delimitations Change by Research Type?

Yes. Quantitative studies emphasize variables, sample size, and measurement tools. Qualitative studies emphasize context, participant selection, and researcher positionality. STEM studies often add technical parameters, such as equipment specifications or measurement thresholds.

Quantitative, Qualitative, and Mixed Methods

• Quantitative: delimit sample size, variables, instruments, and statistical tests used
• Qualitative: delimit participant selection criteria, setting, and the researcher’s role or perspective
• Mixed methods: delimit how the quantitative and qualitative strands are weighted and combined

STEM vs Social Science Studies

• STEM: delimit equipment, materials, experimental conditions, and measurement thresholds
• Social science: delimit population demographics, cultural context, and data collection period
• Both: justify why the chosen conditions or population best answer the research question

What Common Mistakes Should You Avoid?

The 3 most common mistakes are confusing delimitations with limitations, writing a scope statement that is too vague, and failing to explain why a delimitation was chosen.

• Listing a delimitation without justification, which reads as an unexplained gap rather than a deliberate choice
• Writing scope statements that use broad terms like health, technology, or society without narrowing them further
• Introducing new delimitations after data collection has already begun
• Treating delimitations and limitations as interchangeable terms in the same section
• Omitting scope and delimitations from the Abstract, so reviewers only see them deep in the Methods section

Practical Tips for Students and New Researchers

Here are some practical tips for students working on the scope and delimitations of their own study:

Before you write

• Nail down your research question first. Scope and delimitations should flow from it, not the other way around.
• Draft this section early, ideally during proposal writing, not after data collection. Delimitations decided after the fact look like excuses, not choices.
• Talk to your advisor about which delimitations are defensible for your discipline and timeline before you commit to them in writing.

While you write

• For every delimitation, add one sentence explaining why. “This study includes only public universities” is weak on its own; “this study includes only public universities because funding structures differ significantly from private institutions” is defensible.
• Keep your scope statement to 1-2 sentences in the abstract. If it needs a paragraph, it’s probably not narrow enough yet.
• Avoid vague nouns like “society,” “technology,” or “health” without qualifiers. Ask yourself: which population, which variable, which timeframe?
• Don’t confuse delimitations (your choices) with limitations (things outside your control, like a small sample or missing data). Reviewers notice this mix-up quickly.

Common student pitfalls

• Writing delimitations that are so narrow the study says nothing useful to anyone outside your exact sample.
• Copying a delimitations structure from a paper in a different discipline without checking whether it fits your methodology (qualitative studies need different delimitations than quantitative ones).
• Forgetting to revisit scope and delimitations in the discussion section. This is where you explain how those boundaries shaped what you can and can’t claim.

Quick self-check before submitting

• Can a reader tell exactly who or what your study covers from the abstract alone?
• Does every excluded variable, group, or method have a stated reason?
• Have you kept delimitations and limitations in separate sections?
• Does your discussion section circle back to explain how the scope affected your conclusions?

Frequently Asked Questions

Do all research papers need a scope and delimitations section?

Most theses, dissertations, and journal articles benefit from one, even if it is not a separate labeled section. Many journals fold scope into the Introduction and delimitations into the Methods, rather than using standalone headings.

Is delimitation the same as scope in research?

No. Scope describes what a study covers overall, while delimitations describe the specific choices made to narrow that scope, along with the reasons behind each choice.

Where do delimitations go in a thesis?

Delimitations are usually placed in Chapter 1, alongside the research aims and questions, and then referenced again in the Methods and Discussion chapters.

Can delimitations be changed after data collection begins?

Delimitations should be set before data collection starts. Changing them afterward can undermine a study’s credibility, since the delimitations are meant to reflect decisions made during planning, not adjustments made to fit the data.

How long should a scope and delimitations section be?

A typical scope and delimitations discussion runs 150 to 400 words across the Introduction and Methods sections combined, though the exact length depends on the discipline and the journal’s or institution’s requirements.

Do qualitative studies need delimitations?

Yes. Qualitative studies still need delimitations covering participant selection, setting, and the researcher’s perspective, even though they do not rely on variables and sample size in the way quantitative studies do.

What is the difference between delimitations and exclusion criteria?

Exclusion criteria are a specific, often clinical, subset of delimitations that define which participants are ineligible for a study. Delimitations are the broader category, covering variables, setting, timeframe, and methodology as well as participants.

Can a study have too many delimitations?

Yes. Excessive delimitations can narrow a study so much that its findings apply to almost no one beyond the exact sample studied, which weakens external validity and generalizability and can raise questions about the study’s practical value.

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This article was originally published on July 25, 2023, and updated on July 12, 2026.