IB Psychology · Paper 3 guide (HL)
IB Psychology Paper 3 (2027): the four questions, with worked answers
IB Psychology Paper 3 is HL only: 1 hour 45 minutes, 30 marks and 30% of the HL grade. You answer four questions on a set of sources about one HL extension: a 3-mark question on a graph, a 6-mark data analysis, a 6-mark question on credibility, bias or transferability, and a 15-mark synthesis using at least three sources.
Checked against the IB Diploma Psychology guide (first assessment 2027) — October 2026
Paper 3 at a glance
| Question | What it asks | Marks |
|---|---|---|
| Q1 | Explain one issue that limits how a graph can be interpreted | 3 |
| Q2 | Analyse the findings of one source and state a conclusion | 6 |
| Q3 | Discuss credibility, bias or transferability in one source | 6 |
| Q4 | Use at least three sources and your own knowledge to discuss a claim | 15 |
30 marks in 1 hour 45 minutes; HL only, 30% of the HL grade. The sources are all on one of the three HL extensions: the role of culture, motivation or technology. Q4 is half the paper, so leave it at least 45 minutes; that split is our suggestion, not an IB rule.
Our practice sources
Paper 3 is easiest to learn by doing. These three sources are made up for this guide: the studies, numbers and people do not exist. They sit in the technology extension.
Q1: one issue with the graph (3 marks)
Practice question: Explain one issue that limits the interpretation of Source A. [3]
The data in Source A is self-reported.
Why 1: a correct issue, named and nothing more.
Sleep in Source A is self-reported, so teenagers who are online late may misjudge how long they actually sleep. The 1.2-hour gap between the lowest and highest use groups could therefore partly reflect reporting error rather than a real difference in sleep.
The one change: it says what the issue does to the reading of this graph.
Q2: analyse the findings (6 marks)
Practice question: Analyse the findings of Source B and state a conclusion. [6]
Students who stopped using their phones fell asleep 18 minutes faster. This shows phones are bad for sleep.
Why 3: the main finding is reported accurately, but the comparison group is ignored and the conclusion claims more than the study tested.
In the second fortnight the no-phone group fell asleep 18 minutes sooner on average, while the group that kept their phones showed no change. Because both groups were tracked over the same weeks, the difference is unlikely to be due to the time of term, and the trackers avoid the self-report problem in Source A. The conclusion this supports is narrow: removing phone use in the hour before bed shortened time to fall asleep in this sample, which suggests late use, rather than total use, delays sleep.
The one change: the conclusion is built from the comparison in the data and stays as narrow as the study allows.
Q3: credibility, bias or transferability (6 marks)
These are the qualitative research considerations, not reliability and validity.
Practice question: Discuss the transferability of the findings in Source C. [6]
The sample is only 12 people so it cannot be generalised to all teenagers.
Why 2: it treats transferability as statistical generalisation and doesn’t use the source’s details.
Transferability asks whether findings could apply in a similar setting, judged by how fully the setting is described. Source C comes from one boarding school, where students share rooms and phone rules may be set by staff, so the “fear of missing out” in group chats might be stronger or weaker than for teenagers at home. Without a description of those rules, a reader cannot tell how far the findings carry to day students.
The one change: transferability is defined correctly and tested against specific details of the source.
Q4: the 15-mark synthesis
Q4 gives you a claim and asks you to discuss it using at least three of the sources and your own knowledge. It is marked on the same five-band ladder as the other 15-mark questions, and the deciding link is between the sources and the claim, not the topic in general.
Practice question: “Social media use harms adolescents’ sleep.” Using at least three sources and your own knowledge, discuss the validity of this claim. [15]
Source A shows that teenagers who use social media more sleep less. Source B shows that stopping phones before bed helps sleep. Source C shows some teenagers are kept awake by group chats. Therefore the claim is valid, although Source C also says some find scrolling relaxing.
What holds it back: each source is summarised in turn and then agreed with. The sources are never weighed against each other, and the counter-view is tacked on.
The sources support a narrower claim than the one given. Source A links heavy use to shorter sleep, but it is correlational and self-reported, so it cannot show which comes first. Source B is the strongest evidence of harm because it manipulated phone use and measured sleep objectively, yet it only tested use in the hour before bed. Source C suggests why timing matters, since group chats kept some students awake, while others used scrolling to wind down. Taken together, the evidence supports the claim that late-night use can delay sleep, not that social media use in general harms it.
The one change: the sources are ranked by how strongly they bear on the claim, and the conclusion rewrites the claim to fit what they actually show.
Marks shown are our own illustrative marks. The band ladders are our plain-English wording of the IB’s structure, not the IB’s markband text. All sources, questions and answers on this page are written by Markaroo.
Where Paper 3 marks are lost
- Q1: naming an issue without explaining it. “It’s self-reported” is 1 mark. Say how it changes what the graph can tell you.
- Q2: a conclusion bigger than the data. Conclude only what the findings show, and say how they show it.
- Q3: reliability and validity instead of the qualitative terms. The question is about credibility, bias or transferability.
- Q3: no evidence from the source. Point to a specific detail in the source every time.
- Q4: fewer than three sources. The question asks for at least three. Using two makes the top band hard to reach.
- Q4: discussing the topic, not the claim. Keep returning to the exact claim and judge it.
Paper 3 questions
Is IB Psychology Paper 3 HL only?
Yes. Only HL students sit Paper 3. It is 1 hour 45 minutes, 30 marks and 30% of the HL grade.
What is on IB Psychology Paper 3?
Four questions on a set of sources about one HL extension (the role of culture, motivation or technology): a 3-mark question on a graph, a 6-mark data analysis, a 6-mark question on credibility, bias or transferability, and a 15-mark synthesis.
How many sources do you need for the Paper 3 synthesis question?
At least three, plus your own knowledge, to discuss the claim in the question. Answers that use fewer sources struggle to reach the top band.
What are credibility, bias and transferability?
They are the research considerations used for qualitative studies. Credibility is how far the findings reflect what participants meant, bias is anything that skews how data was collected or read, and transferability is whether findings could apply in a similar setting.
Can Markaroo mark my Paper 3 answers?
Yes. Each answer is marked against the band ladder for its question, with a mark, the reason for it and the one change that moves it up. The free plan includes 2 written answers marked free.