How to Write the Introduction Chapter of an MD/MS Thesis

The Introduction is the first chapter an examiner reads, and it sets their expectations for everything that follows. In a few pages it has to answer one question: why did this study need to be done, here, now? Many MD, MS and DNB theses open with a page of textbook definitions and history, and the actual reason for the study appears only in the last line. Examiners notice.

This guide shows you a simple funnel structure that moves from the size of the problem to your specific aim, explains how the Introduction differs from the Review of Literature, and gives you a paragraph-by-paragraph skeleton you can fill in with your own topic.

1What the Introduction Is For

Think of the Introduction as the argument for your study. By the end of it, the reader should accept three things:

• The problem matters – it is common, serious, costly or under-recognised in your setting.
• Something important is still unknown – there is a specific gap in the evidence, not just “few studies have been done”.
• Your study is a sensible way to fill that gap – the design, population and setting fit the question.

Everything else – detailed anatomy, classification systems, long lists of previous studies – belongs in the Review of Literature, not here. The Introduction is short and directional; it points the reader straight at your aims and objectives.

2The Funnel Structure: Burden to Aim

A funnel starts broad and narrows to a point. For a thesis Introduction, that point is your aim. Five steps are usually enough.

Step 1: The burden of the problem

Open with the condition or clinical problem and why it matters. Use figures only from sources you have actually read and can cite – global or national reports, national surveys, or published Indian studies. If you cannot find a reliable number for your setting, say so honestly rather than borrowing a figure from an unrelated population. One or two sentences on burden are enough; this is not an epidemiology chapter.

Step 2: What is already known

Summarise, in a few sentences, the current understanding: how the condition is usually diagnosed or treated, which risk factors or markers are established, and where your variable of interest fits in. Cite key studies, but do not describe each one in detail – that is the Review of Literature’s job.

Step 3: The gap

This is the most important paragraph. State precisely what is not known. Useful kinds of gaps include:

• Evidence exists mainly from other countries or populations, and may not apply to Indian patients.
• Previous studies used a different definition, cut-off, dose or outcome.
• Results of earlier studies conflict.
• A newer, cheaper or simpler test or technique has not been compared with the standard in a setting like yours.
• No study has looked at this question in your region, level of hospital or age group.

Avoid the weak version: “Very few studies have been done on this topic.” Instead write what those studies did not cover.

Step 4: The rationale

Explain why filling this gap would be useful: it could change how patients are screened in your department, support a cheaper test in a resource-limited setting, help counsel patients, or provide baseline data for future trials. Keep the benefit realistic – a single-centre study of limited size will not “change national policy”.

Step 5: The aim

End with one clear sentence that states what the study set out to do. The detailed objectives usually follow under their own heading, as your university format requires. See our guide on how to write aims and objectives so that the last line of your Introduction matches your objectives in meaning.

3How Long Should the Introduction Be?

There is no single national rule. Some universities specify page or word limits for each chapter in their thesis guidelines; many leave it to the guide and department. In practice, the Introduction is usually one of the shortest chapters in the thesis – often a few pages rather than a long chapter – because detail is carried by the Review of Literature.

To decide for your own thesis:

• Check your university’s thesis guidelines or the format circulated by the department.
• Look at two or three recently accepted theses from your department in the library.
• Ask your guide whether they prefer a brief Introduction with a separate “Need for the study” heading, or one combined chapter.

Whatever the length, every paragraph should earn its place. A tight, well-referenced Introduction reads better than a long one padded with definitions.

4Introduction vs Review of Literature

Overlap between these two chapters is one of the commonest structural problems in a thesis. The table below shows how to divide material.

A useful rule: if you have described a study’s sample size and methods, it belongs in the Review of Literature. In the Introduction, you cite its conclusion and move on. For how to organise the longer chapter, read our guide on how to write the Review of Literature.

5A Worked Skeleton with Placeholders

Replace the text in square brackets with your own content. Each numbered item is roughly one paragraph. The wording is a starting point – rewrite it in your own words so that it reads naturally and passes your similarity check.

1. Burden: “[Condition] is a [common / serious / increasingly recognised] problem in [population], associated with [key consequences such as mortality, disability, hospital stay or cost].[ref] In India, [what reliable data show, with source], although data from [your region / level of care] are limited.”
2. Current understanding: “[Condition] is currently diagnosed / managed by [standard approach].[ref] [Variable or intervention of interest] has been proposed as [a marker / an alternative / an adjunct] because [brief mechanism or reason].[ref]”
3. What earlier studies show: “Studies from [settings] have reported [general direction of findings – for example, an association between X and Y].[ref, ref] However, these studies [differed in population / used a different cut-off / were small / reported conflicting results].[ref]”
4. The gap: “There is limited evidence on [specific question] among [your population] in [your setting]. In particular, [what exactly is unknown].”
5. Rationale: “Information on [specific question] could help [clinicians in similar settings / your department] to [screen earlier / choose between options / counsel patients], and may provide a basis for larger studies.”
6. Aim: “Therefore, the present study was undertaken to [study / compare / evaluate] [variable or intervention] in [population] attending [department, institution].”

Example in brief (hypothetical topic)

For a hypothetical study on vitamin D levels in children with recurrent wheeze, paragraph 1 would describe how common and troublesome recurrent wheeze is in young children, citing a source you have verified. Paragraph 2 would summarise the proposed role of vitamin D in airway immunity. Paragraph 3 would note how the published studies differ in population and in the deficiency cut-offs they use. Paragraph 4 would state what is not known about children attending paediatric outpatient departments in your region. Paragraph 5 would explain how the findings could guide testing or supplementation decisions. Paragraph 6 would give the aim in one sentence.

6Common Mistakes and How to Fix Them

Two more checks before you submit. First, reference numbering: in Vancouver style, the Introduction usually contains the first citations of the thesis, so the numbers start here and run in order of first appearance – our Vancouver referencing guide explains how to keep this consistent. Second, tense: background facts are usually written in the present tense, while your own study is described in the past tense in the final thesis (“the present study was undertaken”), even if your synopsis used the future tense.

7Getting Help with Your Introduction

A focused Introduction makes the whole thesis easier to read and defend. If you would like someone to check whether your gap is clearly stated, trim overlap with your Review of Literature, or verify that your opening figures come from real, citable sources, the PubMedico team can review your draft. Message us on WhatsApp at +91 78787 33004.