AREDS Simplified Severity Scale (Macular Degeneration)
The AREDS simplified severity scale (Ferris and colleagues 2005, AREDS Report No. 18) counts risk factors ACROSS BOTH EYES and reads off an approximate FIVE-YEAR risk of advanced age-related macular degeneration…
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Right eye - Advanced disease already present in this eye
- No
- Right eye - One or more large drusen
- Yes
- Right eye - Any pigment abnormality
- No
- Left eye - Advanced disease already present in this eye
- No
- Left eye - One or more large drusen
- Yes
- Left eye - Any pigment abnormality
- No
- Intermediate drusen in BOTH eyes
- No
Result: 12
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Unit
- THE SCALE SCORES A PERSON, NOT AN EYE. Both eyes contribute, so the total runs 0 to 4. Scoring one eye and reporting 0 to 2 is a different instrument.
- Per eye
- 1 factor for one or more large drusen (at or above 125 micrometers, about a large vein width at the disc margin) and 1 for any pigment abnormality.
- Advanced eye
- ASSIGNED 2 FACTORS OUTRIGHT, and its own drusen and pigment are NOT counted - it has already converted. The rest comes from the fellow eye.
- Intermediate drusen
- ONE factor FOR THE PERSON, and only when NEITHER eye has large drusen. Unavailable the moment either eye has large drusen.
- 0 factors
- About 0.5% five-year risk of advanced disease in at least one eye.
- 1 factor
- About 3%.
- 2 factors
- About 12%.
- 3 factors
- About 25%.
- 4 factors
- About 50%.
- Spacing
- NOT evenly spaced: the first step multiplies risk about sixfold, the last two roughly double it. The count is not linear severity.
- Both advanced
- No at-risk eye remains, so no risk is reported. The intermediate factor is also not added there, which would otherwise total 5.
- Scope
- Group-level five-year risk from an examination. Does not diagnose, does not grade existing disease, does not decide supplementation or injection, and does not predict one person.
What you enter
- Right eye - Advanced disease already present in this eye - neovascular disease or central geographic atrophy.
- Right eye - One or more large drusen (at or above 125 micrometers, about the width of a large vein at the disc margin).
- Right eye - Any pigment abnormality.
- Left eye - Advanced disease already present in this eye - neovascular disease or central geographic atrophy.
- Left eye - One or more large drusen (at or above 125 micrometers, about the width of a large vein at the disc margin).
- Left eye - Any pigment abnormality.
- Intermediate drusen in BOTH eyes.
Full field descriptions
- Right eye - Advanced disease already present in this eye - neovascular disease or central geographic atrophy. If yes, this eye is assigned 2 factors and its own drusen and pigment are NOT counted.
- Right eye - One or more large drusen (at or above 125 micrometers, about the width of a large vein at the disc margin). Worth 1 factor for this eye.
- Right eye - Any pigment abnormality. Worth 1 factor for this eye.
- Left eye - Advanced disease already present in this eye - neovascular disease or central geographic atrophy. If yes, this eye is assigned 2 factors and its own drusen and pigment are NOT counted.
- Left eye - One or more large drusen (at or above 125 micrometers, about the width of a large vein at the disc margin). Worth 1 factor for this eye.
- Left eye - Any pigment abnormality. Worth 1 factor for this eye.
- Intermediate drusen in BOTH eyes. Worth 1 factor FOR THE PERSON, and ONLY when neither eye has large drusen.
How this is calculated
Ferris FL, Davis MD, Clemons TE, et al. A simplified severity scale for age-related macular degeneration: AREDS Report No. 18. Arch Ophthalmol. 2005;123(11):1570-1574. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.