The current IB SEHS IA criteria assess the scientific investigation through four equally weighted areas: Research design, Data analysis, Conclusion, and Evaluation. Each criterion is worth 6 marks, giving a total of 24 marks, and the investigation contributes 24% of the final SEHS grade at both SL and HL.
Markers do not award marks simply because a report contains the expected headings. They assess the reasoning within each section, including whether methodological decisions are explained, data are processed accurately, conclusions follow from evidence, and limitations are evaluated according to their impact.
IB SEHS IA criteria at a glance
The official name of the IA is the scientific investigation. It is an open-ended investigation in which you collect and analyse data to answer a research question you have formulated.
| Criterion | Marks | Central marking question |
|---|---|---|
| Research design | 6 | Is the question appropriately contextualised, and is the method justified and reproducible? |
| Data analysis | 6 | Are relevant data recorded, processed, and presented clearly and accurately? |
| Conclusion | 6 | Is the question answered using the analysis and accepted scientific context? |
| Evaluation | 6 | Are specific limitations evaluated and matched with realistic improvements? |
| Total | 24 |
Your teacher initially marks the report, after which the IB externally moderates the school’s marking. The same criteria apply at SL and HL, so HL students do not receive a separate IA rubric.
The report has a maximum of 3,200 words. The official subject guide excludes charts, diagrams, data tables, equations, calculations, citations, the bibliography, and headers from that count. The IB recommends approximately 10 hours of teaching time for the investigation, although independent planning, data collection, and writing may require additional time.
Understanding the mark bands
Each criterion uses three mark bands. The exact descriptor differs by criterion, but the progression is consistent.
| Band | General standard |
|---|---|
| 1-2 | Relevant elements are stated, but reasoning, precision, or supporting evidence is limited. |
| 3-4 | Relevant elements are described with some explanation, although important gaps or inconsistencies remain. |
| 5-6 | Decisions and claims are explained clearly, supported by evidence, and consistently appropriate to the investigation. |
Markers use best-fit judgment, not a mechanical checklist. After selecting the most appropriate band, they decide whether the work merits its lower or upper mark. A single excellent graph cannot secure 6 for Data analysis if processing and uncertainty remain weak.
Use the current syllabus, not the old rubric
Older resources may describe five criteria: Personal engagement, Exploration, Analysis, Evaluation, and Communication. These belong to the previous SEHS course and are not the criteria for the syllabus first assessed in 2026.
Personal engagement is no longer separately marked. Communication and independent decision-making still matter, but they are demonstrated through the four current criteria. Conclusion and Evaluation together provide 50% of the available IA marks, so a detailed method cannot compensate for weak interpretation.
Limited collaboration may be permitted when appropriate. Students may share a similar methodology, but relevant variables must differ where required, each student must obtain unique data, and every report must be written independently.
Research design, 6 marks
Research design assesses how effectively you communicate the purpose and methodology of the investigation. The marker is essentially asking whether the study has a precise SEHS purpose and whether another researcher could reproduce it.
A strong research question identifies the variables, population, measurement approach, and sporting, exercise, or health context. For example, “How does a 10-minute moderate-intensity cycling warm-up affect 20 m sprint time in trained female football players aged 16-18?” is more precise than “Does warming up improve sprinting?”
Important methodological decisions may include:
- participant selection and inclusion criteria
- independent and dependent variables
- sample size, repetitions, and testing order
- controlled variables and standardised instructions
- equipment precision and calibration
- consent, confidentiality, safety, and participant welfare
Top-band work explains these decisions rather than merely listing them. Stating that participants rested for five minutes describes the method. Explaining that this interval reduces variation caused by incomplete recovery shows why the control supports validity.
A reproducible procedure needs exact timings, distances, intensities, units, equipment, and measurement processes. The RevisionDojo SEHS IA guide provides a useful framework for checking this evidence.
Data analysis, 6 marks
Data analysis assesses whether recorded and processed data answer the research question clearly, precisely, and accurately. Markers should be able to trace important processed results back to the raw measurements.
This normally requires consistent units, suitable decimal places, sample calculations, processed data tables, correctly labelled graphs, and interpretation of statistical output. Descriptive statistics such as means and standard deviations are often useful because SEHS participant data commonly show biological variation.
Any statistical test must match the design. Repeated measurements from the same participants may require a paired test, while separate groups may require an unpaired test. Correlation can assess an association between continuous variables, but it does not establish causation. Reporting a p-value without explaining what it means for the research question is insufficient.
Uncertainty includes more than instrument resolution. Reaction time, participant variation, repeated-measure variation, and inconsistent effort can all affect confidence in the result. Error bars must be identified clearly, for example as standard deviation, standard error, or confidence intervals.
Graph choice should follow the question. Scatterplots usually suit relationships, while comparison plots can show differences between conditions. RevisionDojo’s guide to SEHS statistics and evaluation explains common analytical choices.
Conclusion, 6 marks
Conclusion assesses whether you answer the research question using your analysis and the accepted scientific context. It also rewards a clear explanation of the practical implications.
Begin with a direct answer, then support it using selected processed values, the direction and magnitude of the effect, variation, and statistical evidence where appropriate. Do not repeat the entire results table. Claims must remain limited to the tested participants and conditions.
Accepted scientific context may come from peer-reviewed studies, reputable textbooks, established theories, or reliable reference data. Explain whether your findings agree with published evidence and why the result is physiologically, biomechanically, or psychologically plausible. Merely stating that your result agrees with another study does not justify the conclusion.
Practical implications must also follow from the evidence. A small improvement produced by one warm-up protocol might inform coaching for a similar population, but it cannot justify a universal recommendation for all athletes.
Evaluation, 6 marks
Evaluation assesses your judgment of methodological weaknesses and proposed improvements. Generic statements such as “human error affected the results” do not identify what happened or how it influenced the evidence.
For each important limitation:
- Identify the specific problem.
- Explain its effect on the data.
- Judge its importance relative to other limitations.
- Propose a realistic improvement.
- Explain how that improvement addresses the problem.
The phrase relative impact is central to the top band. Explain whether a limitation reduced precision, introduced bias, weakened validity, lowered reliability, or restricted the scope of the conclusion.
For example, inconsistent encouragement could alter maximal effort between sprint trials and increase within-participant variation. A standardised script, automated audio cues, and familiarisation trials would reduce this problem. Similarly, “use more participants” is incomplete unless you explain how a larger, appropriately sampled group would reduce the influence of individual variation or broaden the conclusion.
More participants cannot correct a miscalibrated instrument, so every improvement must address the actual cause. The RevisionDojo evaluation guide develops this limitation-impact-improvement structure.
Common reasons marks are lost
- using the old five-criterion rubric
- listing controls and decisions without explaining them
- including large data tables that do not answer the question
- choosing statistical tests without considering the design
- reporting means while ignoring variation
- making causal or universal claims from limited evidence
- writing generic limitations such as “human error”
- neglecting scientific context or practical implications
Current SEHS IA exemplars can show how evidence is organised, but always check that an example follows the syllabus used for your assessment session. The SEHS lab report guide is useful for reviewing tables, graphs, controls, and scientific explanations.
Conclusion
The current IB SEHS IA criteria reward one coherent scientific argument. Your research question should guide the method, your method should produce relevant data, and your analysis should support a justified conclusion and focused evaluation.
Before submitting, check whether every major decision and claim has an explanation. RevisionDojo’s SEHS IA rubric grader can identify missing criterion evidence, while the IA guide and exemplars can support a final structural review.
Sources and referenced URLs
- IB Sports, exercise and health science subject brief, first assessment 2026
- Official IB SEHS curriculum updates
- RevisionDojo IB SEHS IA guide
- RevisionDojo SEHS IA rubric grader
- RevisionDojo SEHS statistics and evaluation guide
- RevisionDojo IA evaluation guide
- RevisionDojo SEHS IA exemplars
- RevisionDojo SEHS lab report guide