CAT4, MidYIS, the 11+ and the ISEB Common Pre-Test all get shortened to "the test" by parents comparing notes at the school gate — but they are four different assessments, from three different organisations, for three different purposes. Two are internal and change nothing about where your child goes to school. Two decide it.
Why parents mix these four up
The confusion is understandable. All four are reasoning-heavy, multiple-choice-style assessments sat by children roughly aged 10–13. Schools rarely explain which one a child is about to sit or why, and CAT4 and MidYIS come from organisations that themselves sit close together — CEM (the publisher of MidYIS) has been part of Cambridge Assessment, the same family as Cambridge University Press & Assessment, since 2019, having been acquired jointly from Durham University. That single fact trips up a lot of otherwise-accurate advice online, which still describes CEM as a Durham University unit.
The one distinction that matters more than any other: CAT4 and MidYIS are internal school tools. The 11+ and the ISEB Common Pre-Test are external admissions tests that decide which secondary school your child can join. Nothing about a CAT4 or MidYIS score, on its own, gets a child into or keeps a child out of any school.
The four tests at a glance
| Test | Who publishes it | What it's actually for | Who sits it | Admissions or internal? | Pass/fail? |
|---|---|---|---|---|---|
| CAT4 | GL Assessment | Reasoning profile used for setting, target-setting and spotting a mismatch between potential and classroom attainment | Whole year groups at subscribing schools, usually Year 7 (sometimes Year 9) | Internal to the school | No — a profile of scores, not a pass/fail result |
| MidYIS | CEM, part of Cambridge Assessment | Baseline reasoning score used to predict expected progress and set GCSE target grades | Whole year groups at subscribing schools, Years 7–9 | Internal to the school | No — informational, feeds target-setting |
| 11+ | GL Assessment, the CEM family, or a regional body (e.g. Kent, or the Essex CSSE consortium) depending on area | Selects which pupils are offered a grammar school place | Only families actively applying to a grammar school, at the end of Year 6 | External — admissions | Effectively yes — a qualifying score decides eligibility |
| ISEB Common Pre-Test | ISEB (Independent Schools Examinations Board) | Adaptive screening test used to make conditional offers for independent senior school entry at 13+ | Only families applying to an ISEB-linked independent senior school, in Year 6 or 7 | External — admissions | Score-based; feeds a conditional offer rather than a single pass mark |
CAT4 — a reasoning profile for the school, not for entry
CAT4 (the Cognitive Abilities Test, Fourth Edition) measures verbal, non-verbal, quantitative and spatial reasoning to give a school a subject-neutral picture of how a pupil thinks. It is not curriculum-based, has no pass mark, and most schools sit their entire Year 7 intake through it in the first half-term simply to inform setting and support. It is worth noting that a handful of independent and grammar schools do borrow CAT4, or a very similar reasoning test, as part of their own bespoke 11+ or 13+ entrance assessment — so it is not impossible for a CAT4-branded paper to appear in an admissions context. But that is the exception; for the vast majority of children who sit CAT4, it is a purely internal, already-enrolled-pupil exercise. If your child is sitting CAT4 at their current school in Year 7, it is not deciding where they go next — they are already there.
MidYIS — CAT4's sibling, also internal
MidYIS (Middle Years Information System) is CEM's baseline assessment for Years 7 to 9, and it plays a very similar internal role to CAT4: a reasoning-based baseline score used to predict likely GCSE outcomes and monitor progress against that prediction over time. Because CEM also produces some 11+ papers for certain local authorities, parents sometimes assume MidYIS itself must be an entry exam. It isn't. If your child's school mentions MidYIS, it is almost certainly using it exactly as it uses CAT4 — for its own internal target-setting, not to decide entry.
The 11+ — external, and it decides the school
The 11+ is sat at the end of Year 6 by children whose families are actively applying to a selective state grammar school (or, in some areas, an independent school running its own 11+-style paper). Unlike CAT4 and MidYIS, it produces a genuine gatekeeping outcome: a qualifying score, set regionally, determines whether a child is offered a grammar school place. Which organisation sets the paper depends entirely on where you live — GL Assessment, the CEM family, or a local consortium such as Essex's CSSE all run genuinely different 11+ papers with different formats and pass marks, so "the 11+" is really several different regional exams sharing one name.
The ISEB Common Pre-Test — external, and it starts the 13+ process
The ISEB Common Pre-Test is the independent-sector equivalent gatekeeper, though it arrives earlier than most parents expect: most leading senior schools ask candidates to sit it online, adaptively, in Year 6 or Year 7 — well before the main Common Entrance exam at 13 (CE13) in Year 8. It covers maths, English (comprehension and grammar/spelling scored separately) and verbal and non-verbal reasoning, adapting question difficulty to each child's answers as they go, so no two children sit an identical paper. A strong Pre-Test result typically earns a conditional offer years in advance; CE13 later confirms it.
So which one is my child actually sitting?
Ask two questions. First: is this test changing which school my child attends, or is it something their current school is running on everyone in the year group? If it's the latter, it's CAT4 or MidYIS, and there is nothing to prepare for beyond familiarity with the question formats. Second, if it is genuinely deciding a school place: is the family applying to a state grammar school (11+, end of Year 6) or an independent senior school (ISEB Common Pre-Test, Year 6/7, followed by CE13 in Year 8)? That single question resolves almost every case of "which test is my child sitting" confusion.
FAQ
Is CAT4 the same as the 11+?
No. CAT4 is an internal school assessment used for setting and target-setting once a child is already enrolled; it does not decide school entry. The 11+ is an external admissions test that determines whether a child is offered a state grammar school place. A school may use similar-looking reasoning question styles in both, which is where the confusion usually starts.
My child's school mentioned MidYIS — does that mean they're being assessed for grammar school?
Almost certainly not. MidYIS is CEM's internal baseline test for Years 7 to 9, used to predict likely GCSE outcomes and monitor progress — it has nothing to do with grammar school admissions. If your child is applying to a grammar school, that separate process is the 11+, and the school or local authority will tell you directly when and how it is sat.
Why do CAT4 and MidYIS sound so similar to CEM's 11+ papers?
Because CEM, which publishes MidYIS, is also one of the two main national providers of 11+ papers in some local authority areas — and CEM has been part of Cambridge Assessment since 2019, not a standalone Durham University unit as some older articles still describe it. The organisational overlap is real, but MidYIS itself remains a school-internal tool, separate from any 11+ paper CEM produces for a given local authority.
Could my child sit more than one of these four tests?
Yes, and it's common. A child might sit CAT4 in Year 7 at their current school, the 11+ at the end of Year 6 if applying to a grammar school, or the ISEB Common Pre-Test in Year 6/7 if applying to an independent senior school — these are not mutually exclusive, since CAT4/MidYIS run alongside whichever admissions route a family is on, not instead of it.
If your child is preparing for an admissions test — the 11+ or the ISEB Pre-Test — rather than sitting an internal school assessment, targeted one-to-one support can help. Explore aitutors.me to find out more.