QCE Biology IA3 research investigation: how to get top marks
Your IA3 is worth 20% and is marked out of 20, five marks each across four criteria: Forming and Finding, Analysing, Interpreting, and Evaluating. Rather than running an experiment, you evaluate a claim relevant to Unit 4 using secondary evidence you research yourself, and the marks reward how well you compare sources against each other, using multiple credible sources rather than one, not how many sources you simply list.
What the task actually asks
You evaluate a claim relevant to Unit 4, chosen from a list your teacher provides. The task is to research secondary evidence, not to collect your own data, and to reach a justified position on whether the evidence supports the claim.
Conditions. Individual task, roughly 10 hours of class time.
What can be done as a group: selecting the claim, identifying the relevant concepts, and conducting the research. Everything after that, the analysis and the write-up, is yours alone. If you and a classmate researched together but write near-identical interpretation or evaluation sections, that is a problem the individual-work requirement exists to catch.
Since Unit 4 now includes cladistics and phylogeny, claims can be drawn from that content as well as from genetics and heredity, or the continuity of life on Earth.
How it's marked: the criteria, and where students mix up IA2 and IA3
IA3 groups the same five inquiry stages as IA2, Forming, Finding, Analysing, Interpreting and Evaluating, but combines them differently. This is a genuine source of confusion because the two internal assessments pair up opposite stages:
| IA2 Student experiment | IA3 Research investigation | |
|---|---|---|
| Forming | Forming and Finding | |
| Finding | Analysing | |
| Analysing | Interpreting | |
| Interpreting and Evaluating | Evaluating |
So in IA3, Interpreting and Evaluating are separate criteria worth 5 marks each, while in IA2 they are one combined criterion. And in IA3, Forming and Finding are combined into a single criterion, while in IA2 they are separate. If you learned the IA2 structure first, the instinct to expect a combined Interpreting-and-Evaluating criterion here is exactly backwards.
As with IA2, there is no standalone Communication criterion. Genre conventions and referencing are marked inside Forming and Finding.
Forming and Finding: top-band characteristics
QCAA's top-band descriptors for this criterion describe:
- a considered rationale showing clear development of the research question from the claim
- a specific and relevant research question
- selection of sufficient and relevant sources
- appropriate genre conventions
- acknowledgment of sources through referencing
The research question has to develop out of the claim, not restate it. If the claim is a one-line statement your teacher gave the class, your rationale needs to show the thinking that turns it into a question you can actually research and answer.
What counts as a credible source
The syllabus is more permissive than most students assume (p. 47). Credible sources include:
- books and podcasts by well-credentialed scientists
- "popular" science websites or magazines
- websites of governments, universities, independent research bodies, or science and technology manufacturers
- scientific journals
What earns top marks in Analysing, Interpreting and Evaluating
The subject report is specific about what separates strong responses from weak ones (pp. 31-32):
- Trends identified within and between sources. Not just what one source found, but what the same pattern looks like across several, using referenced snips of relevant tables and graphs, sequenced logically.
- Multiple sources. The more sources you use well, the more you can show that the limitations of one are addressed by another, and establish corroboration between them. A conclusion resting on one source cannot corroborate itself.
- Limitations specific to the research question. Not a generic list of weaknesses, but an explanation of how or why each limitation makes the evidence less effective for answering your particular question.
- Evidence quality discussed in terms of bias, currency, relevance and missing data, and how each of those affects how much weight the evidence should carry.
- Accurate terminology. The subject report specifically names gene versus allele as a confusion that costs students marks, and it recurs across multiple report years in Biology more broadly. If your claim touches genetics, know which word you mean before you write it.
- Full referencing. In-text referencing throughout, a consistent style (APA or Harvard, not a mix of both), and a complete bibliography.
The drafting rule
You get one almost-complete draft. This comes directly from the QCE handbook (section 8.2.5), and it is worth knowing early rather than discovering it when you ask for a second round of feedback and cannot get one. Plan your ten hours of class time so that draft happens once, close to finished, not as an early rough cut you expect to revise repeatedly with your teacher.
Common mistakes
Relying on a single strong source instead of several. One good source cannot show corroboration. The report specifically rewards trends found across multiple sources, so a thorough investigation of three or four sources will usually score better than an exhaustive treatment of one.
Writing limitations as a generic list. "This source might be biased" is not a limitation until you say how or why that bias affects the evidence for your specific question. Tie every limitation back to your research question.
Assuming only journal articles are credible. See the credible sources list above. Ruling out government, university and well-credentialed popular science sources narrows your evidence base for no reason the syllabus requires.
Mixing up the IA2 and IA3 criterion structure. IA3 combines Forming and Finding but keeps Interpreting and Evaluating separate. Check which task you are writing for before you plan your response against a remembered criteria list.
Confusing gene and allele. Named explicitly in QCAA's commentary. Check every instance before submitting if your claim touches genetics.
Doing analysis or write-up as a group. Selecting the claim, identifying concepts and researching can be shared. Writing near-identical interpretation or evaluation with a classmate undermines the individual-work requirement.
Inconsistent referencing. Pick APA or Harvard and use it throughout, with in-text citations and a complete bibliography. A mixed or incomplete reference list is graded inside Forming and Finding, so it costs marks even though it looks like a formatting issue.
Assuming a second draft is coming. It is not. See the drafting rule above.
Weak versus strong wording
These pairs follow the distinction the subject report draws between what separates stronger and weaker responses (pp. 31-32), not transcriptions of specific student work.
| Weak | Strong |
|---|---|
| "This source says the claim is true." | Identifying the same trend across several sources and stating that they corroborate each other, or noting where they diverge and why that matters |
| "This might not be a reliable source." | Naming the specific factor, bias, currency, relevance or missing data, and explaining how it affects confidence in this particular claim |
| "One limitation is the sample size." | Explaining why a small sample size specifically weakens the evidence for this research question, not experiments in general |
| "The gene for this trait..." (when describing a specific variant) | Correctly distinguishing the gene from the allele it is being used to describe |
| A reference list with mixed formatting | Consistent APA or Harvard referencing throughout, with in-text citations matching every source used |
Before you submit
- Does your research question develop clearly from the claim you were given?
- Have you used multiple credible sources, not just one, however strong?
- Does every limitation you raise explain how or why it affects evidence for your specific question, rather than restating a generic weakness?
- Have you discussed evidence quality in terms of bias, currency, relevance and missing data?
- Have you checked every use of "gene" and "allele" if your claim touches genetics?
- Is your referencing consistent, in APA or Harvard, with in-text citations and a complete bibliography?
- Did you treat your one draft as close to final, not as a rough first attempt?
See the IA1 data test guide and the IA2 student experiment guide for the other two internal assessments, or head back to the QCE Biology subject page for the full picture of how Biology is assessed.
Frequently asked questions
What is the QCE Biology IA3 research investigation?
It is a research investigation worth 20% of your Biology result. You evaluate a claim relevant to Unit 4, chosen from a list your teacher provides, by researching secondary evidence rather than collecting your own data. It takes roughly 10 hours of class time and is marked out of 20 across four criteria.
How is IA3 different from IA2?
IA2 uses primary data you collect yourself; IA3 uses secondary sources you research. The criteria are grouped differently too. IA2 separates Forming and Finding into two criteria but combines Interpreting and Evaluating into one. IA3 does the opposite: it combines Forming and Finding into one criterion but keeps Interpreting and Evaluating separate.
Do my sources have to be peer-reviewed journal articles?
No. The syllabus also accepts books and podcasts by well-credentialed scientists, popular science websites or magazines, and websites of governments, universities, independent research bodies or science and technology manufacturers. Many students narrow themselves to journals only and miss stronger, more accessible sources.
Can I work in a group for IA3?
For parts of it. The syllabus allows selecting the claim, identifying the relevant concepts, and conducting the research as group activities. The analysis and the write-up must be your own individual work.
How many drafts of IA3 do I get?
One almost-complete draft. The QCE handbook is explicit about this, and it catches students out because they assume several rounds of teacher feedback are available the way they might be for other subjects or other schools.
Sources
- Biology 2025 v1.3 General Senior Syllabus, QCAA, January 2026, p. 47. Internal assessment 3 specifications, conditions, credible source guidance and instrument-specific marking guide.
- Biology subject report, 2025 cohort, QCAA, January 2026, pp. 29-32. Assessment decisions for IA3.
Syllabus and assessment material referenced in this guide is © State of Queensland (Queensland Curriculum and Assessment Authority), licensed under CC BY 4.0. See our QCAA licensing notice. AusGrader is an independent study tool and is not affiliated with, endorsed by, or operated by the QCAA.
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