Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2019 Feb 28;60(3):M20-M30.
doi: 10.1167/iovs.18-25957.

IMI - Defining and Classifying Myopia: A Proposed Set of Standards for Clinical and Epidemiologic Studies

Daniel Ian Flitcroft  1 , Mingguang He  2 , Jost B Jonas  3 , Monica Jong  4 , Kovin Naidoo  4 , Kyoko Ohno-Matsui  5 , Jugnoo Rahi  6 , Serge Resnikoff  4 , Susan Vitale  7 , Lawrence Yannuzzi  8
Affiliations
Review

IMI - Defining and Classifying Myopia: A Proposed Set of Standards for Clinical and Epidemiologic Studies

Daniel Ian Flitcroft et al. Invest Ophthalmol Vis Sci. .

Erratum in

Abstract

Purpose: We provide a standardized set of terminology, definitions, and thresholds of myopia and its main ocular complications.

Methods: Critical review of current terminology and choice of myopia thresholds was done to ensure that the proposed standards are appropriate for clinical research purposes, relevant to the underlying biology of myopia, acceptable to researchers in the field, and useful for developing health policy.

Results: We recommend that the many descriptive terms of myopia be consolidated into the following descriptive categories: myopia, secondary myopia, axial myopia, and refractive myopia. To provide a framework for research into myopia prevention, the condition of "pre-myopia" is defined. As a quantitative trait, we recommend that myopia be divided into myopia (i.e., all myopia), low myopia, and high myopia. The current consensus threshold value for myopia is a spherical equivalent refractive error ≤ -0.50 diopters (D), but this carries significant risks of classification bias. The current consensus threshold value for high myopia is a spherical equivalent refractive error ≤ -6.00 D. "Pathologic myopia" is proposed as the categorical term for the adverse, structural complications of myopia. A clinical classification is proposed to encompass the scope of such structural complications.

Conclusions: Standardized definitions and consistent choice of thresholds are essential elements of evidence-based medicine. It is hoped that these proposals, or derivations from them, will facilitate rigorous, evidence-based approaches to the study and management of myopia.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Variation in the choice of diagnostic thresholds for myopia in terms of spherical equivalent within epidemiologic studies included in meta-analysis (n = 138 studies).
Figure 2
Figure 2
Variation in the choice of the inclusion thresholds for myopia in terms of spherical equivalent within intervention studies (n = 27 studies).
Figure 3
Figure 3
Variation in the choice of thresholds for high myopia within epidemiologic studies (n = 59 studies).
Figure 4
Figure 4
Variation in the choice of high myopia inclusion thresholds within intervention studies (n = 25 studies).
See this image and copyright information in PMC

References

    1. Morgan IG, Ohno-Matsui K, Saw S-M. Myopia. Lancet. 2012;379:1739–1748. - PubMed
    1. Holden BA, Fricke TR, Wilson DA, et al. Global prevalence of myopia and high myopia and temporal trends from 2000 through 2050. Ophthalmology. 2016;123:1036–1042. - PubMed
    1. Huang J, Wen D, Wang Q, et al. Efficacy comparison of 16 interventions for myopia control in children: a network meta-analysis. Ophthalmology. 2016;123:697–708. - PubMed
    1. Wildsoet CF, Chia A, Cho P, et al. IMI – Interventions for Controlling Myopia Onset and Progression Report. Invest Ophthalmol Vis Sci. 2019;60:M106–M131. - PubMed
    1. Rudnicka AR, Kapetanakis VV, Wathern AK, et al. Global variations and time trends in the prevalence of childhood myopia, a systematic review and quantitative meta-analysis: implications for aetiology and early prevention. Br J Ophthalmol. 2016;100:882–890. - PMC - PubMed

Publication types