Charles Boulet, BSc, BEd, OD

The ‘20/20/20 Rule’ – When Good Intentions and Axiomatic Habit Displace Best Practices

publication date
December 5, 2016
see more



Optometrists often proffer the ‘20/20/20 Rule’ as advice for clients who experience nearpoint visual strain, or who are subjected to prolonged expo-sure to nearpoint devices. The ‘rule’ is offered in the patient’s best interests: To help alleviate asthenopia and visual stress from nearpoint strain, and to reduce the risk of onset or the progression of myopia and associated ocu-lar disease. Best intentions aside, there is a paucity of clinical and scientific support for the rule.

On the other hand, modern optical tools and methods, and vision rehabilitation practices are known to be helpful in addressing mild to severe binocular vision disorders, to promote comfort, and to slow the progression of myopia. While offering trite advice to address potentially serious concerns might appear to be helpful, its continued use could well be displacing other more appropriate management strategies. This paper addresses some concerns regarding the promulgation of this well-meaning, but misguided, advice.


The 20/20/20 Rule is a popular optometric axiom that has made its way into popular culture partly, perhaps mostly, due to its promotion by the profession of Optometry. It is intended to promote greater comfort while reading, i.e., to reduce the symptoms of CVS, to abate accommodative hysteresis and NITM, and to prevent myopia or to slow myopic progression. While The Rule’s clinical impact for patients can at best be described as marginal, it will have, in the most extreme cases, no more impact than that of aspirin on a bad fever. The clinician’s role is to diagnose and treat the ill patient; in this case, the patient suffering from nearpoint visual strain, mTBI, or myopic progression. These issues may be addressed through optics, optometric vision rehabilitation, or medical intervention. The Rule alone will not satisfy troubled patients. It is not based on any definable clinical science, nor does it offer any preventive value for healthy and strong readers. Therefore, it should not be given as professional advice per se. Because it provides such limited benefit to the patient, the time taken to explain The Rule is a missed opportunity for advancing further diagnostics, or for exploring more elaborate options for treatment and palliation. While best practice would include some instruction to the patient to take occasional breaks from reading, the value of doing so should not be overstated, nor should the clinician include the erroneous suggestion that this could prevent the onset of structural myopia and associated ocular disease. Optometrists and ophthalmologists need to consider the potential problems with public and professional percep-tions when they offer trite and unproven advice to resolve complex issues. A greater concern is that pithy advice such as The Rule detracts from and marginalizes the proven benefits of Optometric Vision Therapy, such as the level one evidence presented in the Convergence Insufficiency Treatment Trial,30 and it also diminishes the clinical value of a more comprehensive assessment of binocular visual function, which would lead to a more nuanced and valuable clinical result for the patient.

Contact Us To Amplify Your EyeCare

Learn More