COE Clinical Science Exam Study Guide (2026)
Everything the OCANZ COE Written Paper 1: Clinical Science (MCQ) tests, topic by topic: what each section covers, the facts that come up most, and how to study it. Pair it with the free 15-question practice test.
The exam at a glance
| Questions | 144 multiple-choice questions (120 scored, 24 unscored pilot questions), four options each |
|---|---|
| Time | 3 hours (including reading time) |
| Passing score | Not published. OCANZ doesn't announce a fixed pass mark; practise to 70% or higher |
| Format | Closed book, online remote-proctored; no calculators or notes (one blank A4 page allowed) |
| Certifying body | Optometry Council of Australia and New Zealand (OCANZ) |
| Test provider | OCANZ, online with live remote proctoring, taken from home or another suitable place |
Mind map: the whole exam on one screen
Read the complete COE Clinical Science study notes for “Ocular Anatomy, Physiology and Visual Pathways”
Our first full set of comprehensive notes, about 15 minutes of reading: The cornea and why it matters clinically · Extraocular muscles and their nerves · The visual pathway and field defects · Pupils · Aqueous, lens and retina, a worked exam example, the traps examiners use and a one-minute recap. Create a free account to read it and see how premium notes work before you decide.
1. Ocular Anatomy, Physiology and Visual Pathways
The anatomy of the adnexa, eye, visual and pupillary pathways and the extraocular muscles, plus the physiology behind them. Part of the largest competency area in OCANZ's guide (about 18 assessed questions with examination techniques and pathology).
Key facts
- The cornea provides about two-thirds of the eye's refractive power (about 43 D of about 60 D). Its layers: epithelium, Bowman's layer, stroma (about 90% of the thickness), Descemet's membrane and endothelium.
- The corneal endothelium keeps the stroma deturgesced with its Na+/K+-ATPase pump. Adult endothelial cells barely divide, so cell loss leads to oedema once the count falls too far.
- Extraocular muscle supply: LR6 SO4, the rest III. The superior oblique intorts, depresses and abducts; the inferior oblique extorts, elevates and abducts.
- Nasal retinal fibres cross at the chiasm. Chiasmal lesions give bitemporal defects; lesions behind the chiasm give homonymous defects, more congruous the further back they are.
- Temporal lobe (Meyer's loop) lesions give a superior homonymous quadrantanopia; parietal lesions an inferior one. Occipital lesions often spare the macula.
- Pupil: the parasympathetic constrictor path runs with the oculomotor nerve via the ciliary ganglion; the sympathetic dilator path is a three-neurone chain. Horner syndrome: ptosis, miosis and (sometimes) anhidrosis.
- Aqueous is made by the non-pigmented ciliary epithelium and leaves mainly through the trabecular meshwork and Schlemm's canal; the rest drains by the uveoscleral route.
Flashcards
Exam tip: Draw the visual pathway from retina to occipital cortex and mark the field defect for each lesion site. Field-defect questions then take seconds.
2. Optics, Refraction and Spectacles
Vergence, refraction, prismatic effects, lens forms and materials, near additions and dispensing. Spectacles are one of the biggest single areas in OCANZ's guide (about 13 assessed questions), plus about 6 on verifying appliances.
Key facts
- Vergence: L′ = L + F. A lens's power in dioptres is the reciprocal of its focal length in metres.
- Prentice's rule: prism (Δ) = decentration (cm) × power (D). Below the optical centre of a plus lens you get base-up prism; of a minus lens, base-down.
- Effective power at a new vertex distance: Fc = F ÷ (1 − dF), d in metres (shorter distance positive when moving towards the eye). Above about ±4.00 D it changes the contact lens power.
- Transposition: add sphere and cylinder for the new sphere, change the cylinder sign, rotate the axis by 90°. Spherical equivalent = sphere + half the cylinder.
- Vertical prismatic imbalance in anisometropia matters most at the reading level; options include a slab-off (bicentric grinding) on the more minus lens, contact lenses or lowering the optical centres.
- Materials: CR-39 (n ≈ 1.50, Abbe about 58), Trivex (n ≈ 1.53, Abbe about 43-45), polycarbonate (n ≈ 1.59, Abbe about 30). A lower Abbe number means more chromatic aberration in the periphery.
- Amplitude of accommodation falls with age (Hofstetter minimum ≈ 15 − 0.25 × age). Keep about half the amplitude in reserve when calculating a near addition.
Flashcards
Exam tip: There's no calculator in the exam. Practise Prentice, vertex and accommodation sums with round numbers until they take under a minute.
3. Contact Lenses
Patient selection, soft and rigid lens fitting, materials and oxygen, care systems, aftercare and complications. The largest single prescribing area in OCANZ's guide (about 15 assessed questions).
Key facts
- Oxygen transmissibility is Dk/t. Holden and Mertz (1984) proposed about 24 units to avoid corneal oedema in daily wear and about 87 for overnight wear. Silicone hydrogels reach these levels; most conventional hydrogels don't.
- Rigid lens fluorescein patterns: central pooling means the lens is steeper than the cornea (apical clearance); central touch with edge pooling means flatter (apical bearing).
- A good soft lens fit centres, covers the cornea and moves slightly on blink. A tight lens barely moves and may indent the conjunctiva; a loose lens decentres and moves too much.
- Toric soft lens rotation: LARS (left add, right subtract), judged from the observer's view of the marking.
- Hypoxia signs: epithelial microcysts, limbal hyperaemia, stromal oedema (striae, folds) and corneal neovascularisation. The fix is more oxygen: silicone hydrogel, less wearing time, no overnight wear.
- Microbial keratitis: Pseudomonas aeruginosa is the most common bacterial cause; overnight wear is the main risk. Acanthamoeba is linked with water exposure. Painful, central, large or progressing infiltrates need same-day referral.
- Contact lens papillary conjunctivitis (CLPC) shows as papillae on the upper tarsal plate with itch and excess mucus; manage with more frequent replacement, better cleaning or a change of material.
Flashcards
Exam tip: For complication questions, decide first whether it's hypoxic, mechanical, toxic/allergic or infectious. The management follows from the category.
Test yourself on these topics
Take the free 15-question COE Clinical Science test, then save your results to unlock your Readiness Score and the mistakes bank.
4. Ocular Disease and Examination Techniques
Slit-lamp, ophthalmoscopy, tonometry, gonioscopy, fields and OCT, and the diseases they detect: glaucoma, macular disease, vascular occlusions, diabetic retinopathy and emergencies. Part of the largest area in OCANZ's guide (about 18 questions), plus referral urgency and pre- and post-operative care.
Key facts
- Goldmann applanation is calibrated for a central corneal thickness of about 520 µm: thick corneas read high, thin or post-LASIK corneas read low.
- Van Herick grades the peripheral anterior chamber against corneal thickness; grade 1 (less than a quarter) suggests an angle at risk. Gonioscopy confirms the angle structures.
Flashcards
Exam tip: Every disease question has a hidden referral question: know which findings mean same-day, within a week or routine.
5. Ocular Pharmacology and Systemic Health
Diagnostic drugs, basic pharmacology, ocular side effects of systemic medicines and the eye signs of systemic disease. OCANZ assesses this at the non-endorsed level (about 12 questions on medicines plus systemic health items); therapeutic prescribing is assessed in ACOT.
Key facts
- Mydriatics: phenylephrine (alpha-1 agonist, dilates without cycloplegia). Antimuscarinics: tropicamide (short, mild cycloplegia), cyclopentolate (cycloplegic refraction in children), atropine (longest acting).
- Before dilating, assess the anterior chamber angle (van Herick or gonioscopy) and warn about blur, glare and driving.
Flashcards
Exam tip: Learn drugs in pairs: what it does to the eye and what it can do to the body. Questions often test the systemic side.
6. Binocular Vision, Paediatrics and Low Vision
Heterophoria and strabismus, vergence and accommodation anomalies, amblyopia, children's vision, myopia control and low vision devices (about 6 questions on low vision and 3 on vision therapy in OCANZ's guide, with more inside the examination items).
Key facts
- Cover test: a manifest deviation (tropia) shows on the cover-uncover test; a latent one (phoria) only on the alternate cover test.
- Sheard's criterion: the opposing fusional reserve should be at least twice the phoria. Percival's criterion: the near point should sit in the middle third of the vergence range.
Flashcards
Exam tip: In binocular vision cases, classify first (eso or exo, distance or near, basic or excess) before choosing the treatment.
7. Professional Practice, Occupational Vision and Law
Registration and scope, ethics and consent, cultural safety, records and privacy, workplace vision and Australian and New Zealand standards, and fitness to drive. Many small items in OCANZ's guide add up to about 20 questions.
Key facts
- Optometrists in Australia are registered by the Optometry Board of Australia through Ahpra under the National Law; in New Zealand by the Optometrists and Dispensing Opticians Board.
- Prescribing scheduled medicines for therapeutic use needs an endorsement for scheduled medicines on your Australian registration. The COE assesses the non-endorsed level; ACOT covers therapeutics.
Flashcards
Exam tip: These questions are short but easy to overthink. Pick the answer that follows the standard or the law, not what's usual where you trained.
How to pass
- 144 questions in 3 hours is about 75 seconds each, including reading time. Recall questions should take 30 seconds so you bank time for calculations and clinical scenarios.
- Spectacles (about 13 questions), contact lenses (about 15) and eye examination techniques and ocular disease (about 18) carry the most marks in OCANZ's guide. Start there.
- There's no negative marking: answer every question. 24 are unscored pilot items and you can't tell which.
- No calculator is allowed. Practise Prentice's rule, vertex distance and magnification by hand with round numbers.
Frequently asked questions
How long should I study for the COE Clinical Science exam?
Most working candidates need 4 to 8 weeks at 45 to 60 minutes a day. Book your exam once your Readiness Score has stayed at 80 or higher for about a week.
Can I take the COE Clinical Science exam online?
Yes. Both OCANZ written papers are online exams with live remote proctoring, taken from your home or another suitable private room, so you can sit them from your home country. Format: closed book, online remote-proctored; no calculators or notes (one blank a4 page allowed). Check OCANZ's COE Examination Guide for the rules.
What score do I need to pass the COE Clinical Science exam?
Not published. OCANZ doesn't announce a fixed pass mark; practise to 70% or higher. The exam has 144 multiple-choice questions (120 scored, 24 unscored pilot questions), four options each and a time limit of 3 hours (including reading time).
What are the most tested topics?
The outline covers ocular anatomy, physiology and visual pathways, optics, refraction and spectacles, contact lenses, ocular disease and examination techniques, ocular pharmacology and systemic health, binocular vision, paediatrics and low vision, professional practice, occupational vision and law. Use the free practice test to see which ones you need most.
The premium COE Clinical Science study path
Premium COE Clinical Science prep is studied one topic at a time. Each step starts with that topic's key notes and flashcard deck, then its own question sets of 25, so you master one topic before you move to the next. When every topic is strong, the 6 full mock exams show you're ready.
Your step-by-step study path
- 1Ocular Anatomy, Physiology and Visual Pathways9 key notes, 115 flashcards, then 450 practice questions in 18 sets of 25Notes free with an account
- 2Optics, Refraction and Spectacles9 key notes, 115 flashcards, then 425 practice questions in 17 sets of 25Premium
- 3Contact Lenses9 key notes, 115 flashcards, then 425 practice questions in 17 sets of 25Premium
- 4Ocular Disease and Examination Techniques9 key notes, 115 flashcards, then 425 practice questions in 17 sets of 25Premium
- 5Ocular Pharmacology and Systemic Health8 key notes, 115 flashcards, then 425 practice questions in 17 sets of 25Premium
- 6Binocular Vision, Paediatrics and Low Vision8 key notes, 115 flashcards, then 425 practice questions in 17 sets of 25Premium
- 7Professional Practice, Occupational Vision and Law8 key notes, 110 flashcards, then 425 practice questions in 17 sets of 25Premium
- Final step: 6 full mock exams144 questions each, timed like test day. Pass them, then book your exam.Premium
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- The OCANZ Clinical Science paper: every topic, mock exam and flashcard
- 3,000 practice questions + 6 full mock exams per exam
- 800 flashcards + 60 key notes per exam, by topic, plus mind maps
- Spaced repetition + mistakes bank
- Readiness Score & detailed reports
- Video lessons as they release
- Content updates during your access
- 5 bonuses: optometry formulas and values sheet, referral urgency atlas, study planner and more
- Pass Guarantee: complete the prep, pass or 100% back
Renews once a year until you cancel. We email you before each renewal. Cancel any time from your account; you keep access until the end of the year you've paid for.
Summarized from the Optometry Council of Australia and New Zealand's official candidate information and the rules cited, checked November 2026. Confirm current requirements with Optometry Council of Australia and New Zealand (OCANZ).