IBDP Subjects • Internal Assessment • Written by the PrepSeven Editorial Team, reviewed by certified IB Examiners

IB IA Marking Criteria Explained: How Examiners Award Marks

Most students read their subject’s IA criteria once, near the start of the process, and then don’t look at them again until their teacher hands back a marked draft. This is backwards. The criteria aren’t a formality to skim — they’re the actual blueprint examiners use to decide your mark, sentence by sentence, and treating them as a working checklist throughout your research and writing process is one of the highest-leverage habits available to you. This guide, from PrepSeven’s certified and former IB examiners, unpacks the generic markband structure shared across most DP subjects’ IAs, explains what each criterion is really asking for, and shows you how to read your own draft the way an examiner would before you submit it.

Why Understanding Criteria Matters More Than ‘Writing Well’

It’s a common and costly misconception that IAs are marked primarily on writing quality — clarity of prose, vocabulary, how ‘polished’ the report feels. In reality, examiners mark against specific, published criteria with defined markbands, and a plainly written report that hits every criterion precisely will consistently outscore an elegantly written one that misses what a criterion is actually asking for. Understanding the criteria isn’t just useful for revision — it should shape decisions you make from your very first day of research, including what data to collect and how much space to devote to analysis versus background.

The Five Generic Criteria Most DP Subjects Share

While exact wording, mark allocations, and criterion names vary by subject (and you should always check your specific subject’s current official guide for precise details), most DP subjects assess IAs against some version of the following five underlying skills.

Criterion A — Formulating a Focused Question or Aim

This criterion rewards a research question or investigative aim that is specific, answerable, and appropriately scoped for the subject and format. Examiners are checking whether your question actually sets up a clear, feasible investigation, or whether it’s so broad or vague that the rest of your work has no clear direction to follow. A well-formulated question typically identifies the specific variables, population, context, or dataset involved, and often states why the question is worth investigating.

Criterion B — Methodology, Data Collection, and Technique

This criterion assesses whether your chosen method is well-suited to your research question and whether you’ve applied it with appropriate rigour — sufficient trials or sample size, appropriate controls, reliable and relevant sources, or correctly applied subject-specific techniques. In the sciences, this includes things like repeated trials and controlled variables; in economics or business, appropriate and current real-world sources; in mathematics, technically sound and appropriately challenging mathematical methods.

A common misunderstanding is that this criterion only rewards ‘doing more’ — more trials, more sources, more pages of raw data. In reality, examiners are assessing appropriateness and rigour relative to your specific research question, not sheer volume. A smaller, carefully controlled dataset with genuine attention to reliability will outscore a much larger dataset collected without proper care.

Criterion C — Analysis, Application, and Interpretation

This is usually the most heavily weighted criterion across subjects, and it’s where the gap between average and excellent IAs is widest. It rewards genuinely interpreting your evidence — explaining what your data or findings actually mean in relation to your research question — rather than simply presenting results and describing what happened. In quantitative subjects, this includes correctly applying and interpreting statistical or mathematical tools; in qualitative or humanities-based subjects, it includes applying relevant theory or frameworks with genuine insight rather than superficial mention.

Criterion D — Evaluation and Reflection

This criterion rewards honest, specific engagement with the limitations of your method or evidence, and genuine reflection on what your findings mean, what alternative interpretations might exist, and what further investigation could add. A weak response here either ignores limitations entirely, presenting the investigation as flawless, or lists limitations so generic they could apply to almost any study (‘a larger sample size would improve reliability’) without connecting them specifically to your own data or method. A strong response identifies specific, real weaknesses in your own investigation and reasons through their actual likely impact on your conclusions.

Criterion E — Communication and Presentation

This criterion rewards clear organisation, appropriate use of subject conventions (labelled diagrams, correct citation format, appropriate mathematical notation), and overall coherence — a reader should be able to follow your investigation’s logic from question to conclusion without confusion. While typically the smallest-weighted criterion, poor presentation can still meaningfully drag down an otherwise strong IA, since disorganised or unclear communication makes it harder for an examiner to identify the genuine analytical strengths that are present.

How Examiners Actually Read an IA (Not Just Mark It)

It’s worth understanding the practical reading process examiners go through, because it explains why certain structural choices matter so much. Examiners typically read your full IA once for an overall impression, then go back through it criterion by criterion, checking specific sections against specific markband descriptors. This means your research question needs to be clearly identifiable (not buried mid-paragraph), your methodology section needs to be easy to locate and assess independently, and your analysis needs to be distinguishable from your raw results — muddling these sections together makes it harder for an examiner to award marks even when the underlying work is genuinely strong.

Maximising Each Criterion: Practical Tactics

• For Criterion A: state your research question explicitly, early, and in a single clear sentence — don’t make an examiner infer it from context.
• For Criterion B: explicitly justify your methodological choices (why this sample size, why this source selection, why this statistical test) rather than simply describing what you did.
• For Criterion C: after every piece of data or evidence, add at least one sentence of genuine interpretation before moving on — resist the urge to let results ‘speak for themselves.’
• For Criterion D: name specific, real limitations of your own investigation (not generic ones) and reason through their actual likely effect on your conclusions.
• For Criterion E: use clear section headings, label every diagram and table, and apply one consistent citation style throughout.

A Self-Assessment Checklist Before Submission

1. Is my research question stated explicitly and easy to locate in the first section?
2. Have I explicitly justified my methodological choices rather than just describing them?
3. Does every piece of data or evidence have at least one sentence of genuine interpretation attached?
4. Have I identified specific, real limitations of my own investigation, not generic ones?
5. Are my diagrams, tables, and citations correctly labelled and consistently formatted?
6. Could an examiner clearly separate my results section from my analysis section?
7. Have I checked my draft against the actual current official criteria for my specific subject?

Why Checking Your Own Subject’s Current Guide Still Matters

This guide deliberately focuses on the shared underlying logic across DP subjects rather than quoting exact mark allocations or criterion names, because these details are periodically revised by the IB across syllabus updates and differ meaningfully between subjects. Before finalising any IA, confirm the precise current criteria, mark weightings, and markband descriptors for your specific subject and level (SL or HL) directly with your teacher or the official subject guide — the principles above will help you interpret those criteria well, but they’re not a substitute for checking the exact current wording that applies to you.

How PrepSeven Helps You Mark Your Own Work Like an Examiner

PrepSeven’s tutors are certified and former IB examiners who have personally marked IAs against these exact criteria across multiple subjects and sessions. Rather than general feedback on whether your IA ‘reads well,’ we review your draft criterion by criterion, against your subject’s current official markbands, and tell you specifically what would need to change to move from one markband to the next.

• Criterion-by-criterion draft review from tutors who have examined real IAs
• Specific, actionable feedback tied to markband language, not just general writing advice
• Help distinguishing description from genuine analysis in your own draft
• Guidance on writing honest, specific evaluation sections that satisfy reflection-based criteria

Frequently Asked Questions

Q1. What should I do if I scored low on one specific criterion?

Go back to that specific criterion’s descriptors and identify exactly what separates your current markband from the one above it — often the gap is a specific, fixable habit (like adding justification for methodological choices, or naming more specific limitations) rather than a fundamental flaw in your work.

Q2. How important is Criterion D (evaluation) compared to the analysis criterion?

While analysis-focused criteria are typically weighted more heavily, evaluation and reflection criteria are still a meaningful share of your total mark and are often under-developed by students, making them a comparatively easy place to gain marks relative to the effort required.

Q3. Can I ask my teacher exactly which markband my draft is currently in?

Yes — this is a completely reasonable and common request, and most teachers are willing to indicate roughly where a draft currently sits against the criteria, even if they can’t confirm your exact final mark before official submission.

Q4. Do examiners read the whole IA before assigning any marks?

Generally yes — examiners typically read the full response for overall context and coherence before assessing it criterion by criterion, which is exactly why clear organisation and easily locatable sections (research question, methodology, analysis, evaluation) matter so much.

Q5. Is it possible to score highly on analysis but still get an overall low mark?

Yes — because marks are awarded per criterion and then combined, a genuinely strong analysis section paired with a weak or missing evaluation section, poor methodology justification, or unclear presentation can still meaningfully lower your overall IA mark.

Q6. How specific do my limitations need to be in the evaluation section?

Very specific — generic limitations that could apply to almost any study in your subject (‘a larger sample would help’) carry far less weight than limitations tied precisely to your own method, data, or context, along with reasoning about their actual likely impact on your conclusions.

Q7. Should I write my evaluation section before or after my analysis section?

Write your analysis first, then evaluation — genuine evaluation depends on having already worked through your actual findings and interpretations, since strong evaluation reflects specifically on the analysis you’ve just completed rather than existing as a generic, detachable section.