COA Domain 1: History and Documentation (9%) - Complete Study Guide 2026
History and Documentation represents the largest single content area on the COA exam, accounting for 9% of all test questions.
COA Domain Deep Dives
Domain Deep Dives for the IJCAHPO Certified Ophthalmic Assistant (COA) exam - 10 in-depth guides to help you prepare with confidence. Browse all study resources or jump straight into a guide below.
COA Domain 2: Visual Assessment (7%) - Complete Study Guide 2026
Visual assessment represents 7% of the COA exam, making it a critical component that requires thorough understanding and practical application...
COA Domain 3: Visual Field Testing (6%) - Complete Study Guide 2026
Visual field testing represents 6% of the COA examination content and is a critical diagnostic tool in ophthalmic practice.
COA Domain 4: Pupil Assessment (7%) - Complete Study Guide 2026
Pupil assessment represents a critical component of ophthalmic examination, accounting for 7% of the COA certification exam content.
COA Domain 5: Tonometry (7%) - Complete Study Guide 2026
Domain 5: Tonometry represents 7% of the COA exam content, making it one of the more heavily weighted technical domains.
COA Domain 6: Keratometry (2%) - Complete Study Guide 2026
Domain 6: Keratometry represents 2% of the COA examination content, making it one of the smaller domains on the test.
COA Domain 7: Lensometry (3%) - Complete Study Guide 2026
Domain 7: Lensometry represents 3% of the Certified Ophthalmic Assistant (COA) examination, translating to approximately 6 questions out of the total...
COA Domain 8: Biometry Complete Study Guide 2026
Biometry, in ophthalmic practice, refers to the precise measurement of the eye's physical dimensions - most critically the axial length - to calculate...
COA Domain 9: Pharmacology Complete Study Guide 2026
The IJCAHPO Certified Ophthalmic Assistant (COA) examination is built around 22 specific domains, each carrying a defined percentage of the total...
COA Exam Domains 2026: Complete Guide to All 7 Content Areas
Understanding the COA exam domains is the foundation of effective exam preparation. The IJCAHPO Certified Ophthalmic Assistant exam tests knowledge...
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