Final Research Plan
Vision in Children Ages 6 Months to 5 Years: Screening
July 24, 2025
Recommendations made by the USPSTF are independent of the U.S. government. They should not be construed as an official position of the Agency for Healthcare Research and Quality or the U.S. Department of Health and Human Services.
a Amblyopia risk factors include 1) significant differences in vision between the two eyes [anisometropia of hyperopia, myopia, or astigmatism, 2) significant refractive error in both eyes [isometropia of hyperopia, myopia or astigmatism], 3) eye misalignment (strabismus), and 4) conditions that obstruct vision, such as cataracts or ptosis.
b Determination of refractive error will be based on age-appropriate standards.
1. Does screening for amblyopia, its risk factors, and refractive error in children ages 6 months to 5 years reduce long-term amblyopia, improve visual acuity in childhood and/or adulthood, or improve school performance, functioning, and/or quality of life?
2. What is the accuracy and reliability of screening tests for amblyopia, its risk factors, and refractive error in children ages 6 months to 5 years?|
3. What are the harms of screening for amblyopia, its risk factors, and refractive error in children ages 6 months to 5 years?
4a. Does treatment of amblyopia, its risk factors, and refractive error in children ages 6 months to 5 years improve visual acuity in childhood and/or adulthood?
4b. Does treatment of amblyopia, its risk factors, and refractive error in children ages 6 months to 5 years reduce long-term amblyopia or improve school performance, functioning, and/or quality of life?
5. What are the harms of treatment of amblyopia, its risk factors, and refractive error in children ages 6 months to 5 years?
Contextual questions will not be systematically reviewed and are not shown in the Analytic Framework.
- What are the current rates of completion of eye exams and obtaining appropriate treatment for amblyopia, its risk-factors, or refractive error among children with screen-identified vision concerns?
- How do rates of completion of eye exams and obtaining appropriate treatment for amblyopia, its risk factors, or refractive error among children with screen-identified vision concerns vary based on patient characteristics?
To the extent possible, we plan to describe the population, screening modality, and intervention characteristics of the included studies, as appropriate for each key question. Data on population characteristics will help us explore the degree to which the findings are representative of all children as well as investigate potential differences in benefits and harms by different population groups.
The Research Approach identifies the study characteristics and criteria that the Evidence-based Practice Center will use to search for publications and to determine whether identified studies should be included or excluded from the Evidence Review. Criteria are overarching as well as specific to each of the Key Questions. The Table details the eligibility criteria for the evidence review.
| Include | Exclude | |
|---|---|---|
| Populations | All KQs: Children ages 6 months to 5 years
KQs 1–3: Children without known impaired visual acuity or obvious symptoms of impaired visual acuity KQs 4, 5: Children with amblyopia, amblyogenic risk factors, and/or refractive error |
Studies that focus primarily on newborns, children younger than age 6 months, and children aged 6 years and older; children with a history of retinopathy of prematurity, glaucoma, congenital cataract, systemic conditions associated with ocular abnormalities, or pathologic myopia;a children with a history of intraocular surgery, family history of strabismus or amblyopia in a first-degree relative; history of prematurity (<32 weeks) or low birth weight
Studies evaluating screening in specified populations of children with a chronic medical or developmental condition will also be excluded. However, studies that happen to include some children with a chronic condition will be included as long as the presence of the condition was not among the study’s inclusion criteria |
| Setting | All KQs: Studies performed in primary care, community-based, and school settings; studies conducted in countries categorized as “Very High” on the Human Development Index, as defined by the United Nations Development Programme
KQs 2–5: Specialty settings (e.g., ophthalmology or optometry practices) |
All other settings |
| Screening tests and interventions | KQs 1–3: Studies of screening tests used or available in primary care settings, including: autorefractors and photoscreeners currently commercially available, visual acuity tests (e.g., picture identification tests, such as Lea symbols or Allen test cards; HOTV chart; Snellen chart); stereoacuity tests (e.g., the Frisby, Random Dot E, Stereo Smile; Moving Dynamic Random Dot Stereosize test), contour stereotests, such as the Titmus Fly tests, and ocular alignment tests (e.g., corneal light reflex test, pupillary reflex test, cover-uncover test, cross cover test, red reflex test).stereotests, such as the Titmus Fly tests, and ocular alignment tests (e.g., corneal light reflex test, pupillary reflex test, cover-uncover test, cross cover test, red reflex test).
For KQs 2 and 3, studies assessing photoscreeners for screening will be included if the photoscreener being evaluated is in current use. For KQ1, any photoscreener, in use or not, is eligible. KQs 4, 5: Correction of refractive error (eyeglasses, corrective lenses, and low-dose atropine); penalization of the nonamblyogenic eye (eye patch, atropine); vision therapy (eye exercises) |
KQs 1–3: Studies of screening tests not used or available in primary care settings (e.g., contrast sensitivity test, fundoscopic examination, visual acuity test with cyclopegia) or not intended to detect amblyopia, amblyogenic risk factors, or refractive error (e.g., white reflex test)
KQs 2, 3: Studies exclusively assessing photoscreeners not in current use will be excluded (e.g., MTI photoscreener, VisiScreen 100 photoscreener, Otago [noncommercial] photoscreener, off-axis-type photoscreener, Topcon PR2000) KQs 4, 5: Surgical interventions for strabismus or other indications; acupuncture |
| Comparisons | KQs 1, 3: Screened vs. nonscreened groups or earlier (at a younger age) vs. later screening (at an older age)
KQ 2: Evaluations that include cycloplegic refraction and/or a comprehensive eye examination; for evaluations of reliability (test-retest), the comparison may be the same test administered at different timepoints or by a different person KQs 4, 5: No treatment or sham or inactive control |
No comparison; nonconcordant historical controls; comparative studies of various interventions (i.e., head-to-head studies without an additional eligible comparison group) |
| Outcomes | KQs 1, 4: Reduced long-term amblyopia and improved visual acuity, school performance, functioning, and quality of life
KQ 2: Sensitivity, specificity, positive and negative predictive values, likelihood ratios, and diagnostic odds ratios (or ability to calculate such outcomes from data provided); measures of reliability, including reproducibility, interrater reliability, and testability (ability of children to cooperate with the test) KQs 3, 5: Harms, including psychological distress, labeling, anxiety, other psychological effects, false-positive results, and adverse effects on vision in the nonimpaired eye |
Cost-effectiveness or cost-related outcomes
KQ 2: Studies only providing associations, correlations, or other outcomes |
| Study designs | KQ 1: Randomized, controlled trials and prospective cohort studies with an eligible comparator
KQ 2: Cross-sectional studies, cohort studies, or trials focused on assessment of diagnostic accuracy KQs 3, 5: Randomized, controlled trials; controlled cohort studies; case-control studies KQ 4: Randomized, controlled trials |
Case reports, case series, systematic reviews, and all other study designs not listed as eligible; systematic reviews containing potentially relevant studies will be hand-searched for eligible articles
KQ 2: Studies that do not attempt to perform the reference standard in all participants or a random sample of participants |
| Language and Publication status | English-language, full-text journal articles | Languages other than English; publications available only as a conference abstract |
a Pathologic myopia as defined by the International Myopia Institute: “Excessive axial elongation associated with myopia that leads to structural changes in the posterior segment of the eye.”1
The exclusion criteria are detailed in the table above. We are excluding screening strategies that are not available in primary care settings, as well as studies that evaluated photoscreeners that are no longer clinically available. We are not evaluating surgical treatments for vision impairment, and we are not assessing the comparative effectiveness of treatments.
We made the following adjustments to the research plan based on public comments:
- Clarified the included list of amblyopia risk factors.
- Clarified the working definition of refractive error for this review.
- Added studies that focus on children with a history of intraocular surgery, family history of strabismus or amblyopia in a first-degree relative, history of prematurity (< 32 weeks) or low birth weight to the exclusion criteria.
- Included a definition of pathologic myopia.
- Clarified how studies including children with other chronic conditions would be considered in this review.
- Refined the list of eligible screening tests and clarified what types of studies of photoscreeners would be considered for inclusion.
- Flitcroft DI, He M, Jonas JB, et al. IMI - Defining and Classifying Myopia: A Proposed Set of Standards for Clinical and Epidemiologic Studies. Invest Ophthalmol Vis Sci. Feb 28 2019;60(3):M20-m30. doi:10.1167/iovs.18-25957