- Journal List
- American Academy of Pediatrics Selective Deposit
- PMC6317790
As a library, NLM provides access to scientific literature. Inclusion in an NLM database does not imply endorsem*nt of, or agreement with, the contents by NLM or the National Institutes of Health.
Learn more: PMC Disclaimer | PMC Copyright Notice
Pediatr Rev. 2018 May; 39(5): 225–234.
PMCID: PMC6317790
PMID: 29716965
Allison R. Loh, MD* and Michael F. Chiang, MD*†
Author information Copyright and License information PMC Disclaimer
Practice Gap
Incorporating vision screening and a basic eye examination in the primary caresetting can be challenging. Determining which screening examination to perform andwhen to refer a patient to a pediatric eye care provider is critical.
Objectives
After completing this article, readers should be able to:
Understand the importance of vision screening and know what conditionscan be detected by periodic eye examinations.
Describe the components of a vision screening examination at differentages and plan an appropriate evaluation of vision.
Recognize the indications for referral to pediatric ophthalmology.
Introduction
Vision screening is crucial for early detection andprevention of vision loss in young children. Vision screening can be performed byprimary care providers, trained laypersons (eg, school-based screenings), and eyecare providers. Vision screening techniques are either provider-based (eg,traditional acuity testing, inspection, red reflex testing) or instrument-based.Instrument-based screening can often be performed at an earlier age thanprovider-based acuity testing and allows earlier screening for risk factors that arelikely to lead to amblyopia and poor vision. The American Academy of Pediatrics(AAP) and the American Association for Pediatric Ophthalmology and Strabismus havedeveloped guidelines to help practitioners screen for vision problems at differentages (Table 1).
Table 1.
Age-Appropriate Methods for Pediatric Vision Screening and Criteria forReferral
| METHOD | INDICATIONS FOR REFERRAL | RECOMMENDED AGE | ||||
|---|---|---|---|---|---|---|
| Newborn–6 mo | 6 mo until cooperative for vision testing | 3–4 y | 4–5 y | Every 1–2 y after age 5 y | ||
| Red reflex test | Absent, white, dull, asymmetrical | Evaluate at all ages | ||||
| External inspection | Structural anomaly (eg, ptosis, hemangioma) | Evaluate at all ages | ||||
| Pupil examination | Unequal size, poor reaction to light, irregularshape | Evaluate at all ages | ||||
| Corneal light reflex | Asymmetrical or displaced | * | * | * | * | |
| Instrument-based screening | Failed to meet screening criteria | * | * | * | * | |
| Cover test | Refixation movement | * | * | * | ||
| Visual acuity (distance, monocular) | Failure to fixate and follow | Failure to fixate and follow | 20/50 or worse in either eye | 20/40 or worse in either eye | 20/30 or worse or 2-line difference between eyes | |
Open in a separate window
Asterisks indicate the method of vision screening that should beperformed in that age column.
The Importance of Vision Screening
Vision screening allows the early detection of preventablevision-threatening or life-threatening conditions. Amblyopia, colloquially called“lazy eye,” is a reduction of best-corrected visual acuity that is notdirectly caused by any structural abnormality of the eye. It is caused by anabnormal visual experience resulting from strabismus, refractive error, or stimulusdeprivation. Amblyopia occurs in 1% to 4% of children (1) and can be caused by visual deprivation (eg, cataract,ptosis, corneal opacity), strabismus (any form of eye misalignment, such asesotropia or exotropia), high refractive error (eg, hyperopia or myopia), oranisometropia (asymmetry of refractive error between the eyes). Amblyopia is moreeasily and successfully treated the earlier it is detected, and it becomesimpossible to treat after 7 to 9 years of age. Patients and caregivers may beunaware of the consequences of delayed evaluation and treatment. (2) The short window of opportunity to savevision underscores the importance of vision screening to detect amblyopia or itsrisk factors while treatment is still effective. Vision screening assessments inearly childhood reduce the risk of vision loss at age 7 years by more than 50%.(3)
Vision screening and eye examinations within the medical home create frequent andearly opportunities to diagnose a myriad of conditions. In the first year of life,causes of deprivation amblyopia are more frequent and result in the most profoundvision loss. Conditions affecting infants include corneal opacities, cataracts,ptosis, glaucoma, and retinoblastoma. Deprivation amblyopia in infancy can developvery rapidly. A few weeks of deprivation of visual stimulus in 1 eye from a densecataract or complete ptosis can result in profound amblyopia that often requiresyears of numerous hours of patching treatment. Early detection of retinoblastoma cansave the child’s vision and life. Ocular abnormalities may be the firstrecognized sign of a systemic disease. For example, blurred vision and bilateralcataracts in a child can be the first presentation of a neurodegenerative disease,cerebrotendinous xanthomatosis, that if unrecognized causes irreversible cognitiveimpairment. Early recognition and treatment with an oral medication can preventlifelong disability. In addition, a crossed eye may be the first sign of vision lossin a baby with optic nerve hypoplasia as part of septo-optic dysplasia. Effectivescreening by the pediatrician can lead to earlier diagnosis of systemicproblems.
The etiologies of amblyopia vary with age. Form deprivation amblyopia is morefrequent and profound in infants. A unilateral cataract in a newborn will causesubstantial amblyopia if untreated and should be removed within weeks; in contrast,a traumatic cataract in a 6-year-old with previously good vision is much less likelyto cause amblyopia, and in the absence of other damage from the trauma, the cataractcan be removed nonurgently. In children younger than 3 years, strabismus is the mostcommon cause of amblyopia; in children 3 to 6 years old, strabismus andanisometropia contribute equally. (4) Inyounger children (eg, up to age 3 years), the examination is more challenging andthe disorders can be subtle, but early detection can have a profound effect on thechild’s vision and future if treatment is initiated quickly. To detect theseabnormalities, vision screening should be performed by primary care providers ortrained laypersons (eg, school-based screenings) throughout childhood. The combinedsensitivity of a series of screening evaluations is higher than a single evaluation,especially if different methods are used for each screening evaluation. (5) Unfortunately, children present to theophthalmologist at age 6 to 8 years for their first eye examination with significantamblyopia (frequently, anisometropic amblyopia) whose vision loss would have beenpreventable if they had been detected earlier and been prescribed glasses at ayounger age. The routine assessment of vision in all children cannot beoveremphasized; special attention should also be given to children withdisabilities. Children with developmental delay can experience a delay inidentification of their ocular disease that further impedes successfultreatment.
Some children should be referred directly for a comprehensive examination. Forexample, poor eye contact by a term infant with the caretaker after 8 weeks of agewarrants further assessment (8 weeks' adjusted age for premature children).Table 2 lists red flag signs and symptomsfor possible eye problems. Special attention should be given to children with ahistory of a known medical risk factor for vision problems, including prematurity,cerebral palsy, craniofacial abnormalities, Down syndrome, Marfan syndrome,congenital cytomegalovirus, eyelid hemangiomas, Sturge-Weber syndrome, sickle celldisease, and nevus of Ota. Children with medical conditions such as diabetes orjuvenile idiopathic arthritis should receive a comprehensive evaluation soon afterdiagnosis.
Table 2.
Signs and Symptoms of Potential Vision Loss
| SIGN/SYMPTOM | POTENTIAL EYE PROBLEM | PEDIATRIC PROVIDER ACTION |
|---|---|---|
| No eye contact in an infant >8 wk old corrected age | Decreased vision, delayed vision maturation | Vision screen and refer to ophthalmologist |
| Head tilt or face turn | Strabismus, nystagmus, high astigmatism | Vision screen and refer to ophthalmologist |
| Unable to comply with vision screening | Decreased vision | Refer to ophthalmologist |
| Tearing | Congenital nasolacrimal duct obstruction, glaucoma | Age <1 y without other signs of glaucoma (enlarged corneas,photophobia, blepharospasm), vision screen |
| Age >1 y refer to ophthalmology | ||
| Photophobia | Congenital glaucoma, inflammation | Vision screen and consider referral |
| Squinting | Refractive error, strabismus | Vision screen and consider referral |
Open in a separate window
Provider-Based Vision Screening
Red Reflex Testing
The red reflex test is the most important screening testfor infants and young children. Red reflex testing requires no patientparticipation and can be performed shortly after birth. A direct ophthalmoscopeis used to view both eyes simultaneously from 2 to 3 ft away from the patient(Fig 1).
Figure 1.
A. A provider performing red reflex testing approximately 2 to 3 ft fromthe infant. B. The provider's view of bilateral red reflex viewingboth eyes simultaneously.
The red reflex represents reflection of the retina through a clear pupillaryaxis. Distortion in the red reflex can be caused by an abnormality anywhere inthe visual axis (eg, in the retina [retinoblastoma], vitreous [vitreoushemorrhage], lens [cataract], or cornea [scar or infection]). A difference inthe red reflex can also be caused by asymmetry in the refractive power of theeye, which can cause amblyopia and be vision threatening. The AAP recommendsroutine screening for structural abnormalities using red reflex testing. (6) Figure2 represents examples of normal and abnormal red reflex testing.
Figure 2.
Red reflex examination. A. Normal: Child looks at light. Both redreflections are equal. B. Unequal refraction: One red reflection isbrighter than the other. C. No reflex (cataract): The presence of lensor other media opacities blocks the red reflection or diminishes it. D.Foreign body/abrasion (left cornea): The red reflection from the pupilwill backlight corneal defects or foreign bodies. Movement of theexaminer’s head in 1 direction will appear to move the cornealdefects in the opposite direction. E. Strabismus: The corneal lightreflex is temporally displaced in the misaligned right eye, indicatingesotropia. (Reprinted with permission from American Academy ofPediatrics; Section on Ophthalmology; American Association for PediatricOphthalmology and Strabismus; American Academy of Ophthalmology;American Association of Certified Orthoptists. Red reflex examination inneonates, infants, and children. Pediatrics.2008;122(6):1402. Image courtesy of Alfred G. Smith, MD ©1991.)
Red reflex testing allows for the prompt diagnosis of and referral for leukocoria(white pupil), which occurs when there is an opacity preventing a clear view ofthe retina. The most concerning cause of leukocoria is retinoblastoma, alife-threatening tumor in children. All patients with abnormal red reflex testsshould be referred to pediatric ophthalmology, and concern for leukocoria shouldbe urgently referred.
External Examination
The external examination of the eyes, eyelids, and faceis an important part of the visual system screening in a primary care office. Asimple penlight examination of the eyelids can reveal ptosis, capillaryhemangiomas, and port wine stains, which are risk factors for amblyopia andsystemic diseases. Careful inspection of the globe size is important inscreening for pediatric glaucoma, which can cause either unilateral or bilateralocular enlargement. Ptosis requires prompt identification because it can causeamblyogenic astigmatism even if the lid itself does not block the visual axis.Substantial ptosis obstructing the visual axis requires urgent referral in anychild. For subtler ptosis, referral to an ophthalmologist is appropriate forchildren too young to assess vision using either optotypes (figures or lettersof different sizes used to test vision acuity) or instrument-based screening. Inolder children who pass a vision screening with subtle ptosis, referral toophthalmology is not required. Ptosis combined with miosis, which is anasymmetrically constricted pupil, may represent Horner syndrome and wouldrequire an ophthalmology evaluation for neuroblastoma in children. In addition,an enlarged globe (buphthalmos) is caused by elevated eye pressure. Any enlargedeye, especially with a history of tearing and photophobia, should be referredimmediately for concern of pediatric glaucoma. Careful inspection by an astuteprimary care provider is crucial to the early identification ofvision-threatening and potentially life-threatening problems.
Visual Acuity Testing
What is normal visual acuity? Normal acuity changes withage because visual acuity improves as children grow. Infants, 0 to 2 months ofa*ge, should blink in response to bright light and have equal pupillaryresponses. Additional signs of normal vision in infants include the“eye-popping reflex.” For the first year of life, children withnormal vision manifest an eye-popping reflex where the eyelids retract onturning off the lights. It can be clinically helpful to determine that an infanthas at least light perception vision when parents are concerned that their babycannot see. The eyelid retraction disappears when ambient light is turned on,and the phenomenon is thought to be a form of primitive startle reflex. (7) Fixation and tracking should improve andbecome reliable around 6 to 8 weeks of life. Premature children may have somedelay in their visual development and may not fix and follow until theiradjusted age reaches 8 weeks. Newborns may have intermittent strabismus (eithereye turning outward or inward), but this should resolve by 2 to 4 months of age.Any constant strabismus is considered abnormal at any age, and intermittentstrabismus after 4 months warrants referral. From age 6 months to 2 years,children should be able to fix and follow an object monocularly and have normalalignment. After age 3 to 5 years, subjective vision can usually be measuredusing eye charts. Video 1 demonstrates atechnician checking vision in a 2.5-year-old girl using matching LEASYMBOLS® (Good-Lite Co, Elgin, IL) optotypes (standard symbols such asletters or pictures). A practical tip for checking vision in very young childrenis to begin the “matching game” before covering each eye toconfirm understanding and to encourage participation before introducing the eyepatch.
Video 1. Video of a technician checkingvision monocularly in a 2.5-year-old girl using matching LEASYMBOLS® optotypes and an eye patch.
Children 3 years or older typically can participate in provider-based subjectivevisual acuity testing. Children who cannot participate in subjective visualacuity testing are considered untestable, and untestable children have beenshown to have vision problems more often than testable children. (8) Repeated examination in 6 months isrecommended, and inability to assess vision in a 3- to 5-year-old meritsreferral to an eye care provider. (5)Recommendations for referral based on visual acuity are presented in Table 1.
Recognition visual acuity testing is the gold standard in vision screening andthe preferred method for assessing vision to detect amblyopia, especially inolder children. Vision is routinely tested at 2 standard distances (10–20ft for distance vision and 14–16 in for near vision). Vision should bemeasured monocularly, which involves sufficiently occluding 1 eye with anadhesive patch or occlusive tape. Vision should be checked while the child iswearing any necessary corrective lenses. Young children improve performance ifallowed to match optotypes presented on the chart to a handheld card (eg, Video 1). The choice and presentation ofoptotypes on an eye chart affect the visual acuity obtained. The currentrecommendations by the American Academy of Ophthalmology are for LEASYMBOLS® (Fig 3) or HOTV letters to beused as the preferred optotypes for preliterate children. The goal is for theoptotypes to be standardized, clear, and without cultural bias. Allen figures,tumbling E charts, and Lighthouse symbols are not standardized and are no longerrecommended as preferred optotypes.
Figure 3.
LEA SYMBOLS®. (Reprinted with permission from Good-Lite Co, Elgin,IL.)
Cover and Hirschberg Testing for Strabismus Evaluation
A common concern among parents is for strabismus(misalignment of the eyes). An esodeviation refers to a convergent misalignmentof the visual axis. Esophoria is a latent esodeviation that under normalbinocular conditions the eyes remain properly aligned. Esotropia is anesodeviation that is not controlled by fusional mechanisms, so the deviation isconstantly manifest. Exodeviation is a divergent strabismus that can be latent(exophoria) or manifest (exotropia). Most people have some latent strabismus(esophoria and exophoria) that can be revealed by extensive cover testing and isnot amblyogenic, but manifest strabismus is a frequent cause of amblyopia.
Examination techniques such as cover testing and Hirschberg testing are crucialfor evaluating concern for strabismus. For example, parents can report esotropiabut may in fact be appreciating pseudoesotropia. Children with large epicanthalfolds or a flat nasal bridge often have pseudoesotropia (appearance of crossedeyes when the eyes are in fact straight), which may be diagnosed by symmetry ofthe pupillary light reflex when shining a penlight toward the patient or bycover testing (Fig 4). If the primary careprovider is confident in the diagnosis of pseudoesotropia, these patients do notrequire referral to ophthalmology.
Figure 4.
Pseudoesotropia with wide epicanthal folds. Despite the left eyeappearing crossed because there is less white sclera visible nasally,the well-centered light reflexes confirm pseudoesotropia.
The cover-uncover test and the Hirschberg test are used to determine whetherthere is a manifest misalignment of the eyes. The Hirschberg test is a simpletest where a penlight is directed at the patient while he or she is lookingstraight ahead. The light reflex should be reflected in the center of each pupilif the patient’s eyes are straight. If there is a manifest exotropia, thelight reflex will be nasal to the pupil. If there is a manifest esotropia, thelight reflex will be temporal to the pupil (Fig5). The Hirschberg test, along with the cover test, can be veryhelpful in distinguishing a benign pseudoesotropia from a true manifeststrabismus requiring ophthalmology referral.
Figure 5.
Esotropia of the left eye.
The cover test requires the child to fixate either at near (eg, a sticker on anexaminer’s nose or a toy held up close) or distance (eg, a television orparent at the end of the room). If the patient is watching your nose and thereis a manifest exodeviation of the right eye (ie, the right eye is turning out),the left eye is straight and fixating. The cover test involves covering thefixating eye and watching the deviated eye shift toward central fixation. If themisaligned eye is drifted out, the eye will shift inward when the fixating eyeis covered. If the deviated eye is turned in, the eye will shift outward whenthe fixating eye is covered. Video 2demonstrates a child with esotropia whose inward-turned eye refixates outwardwhen his opposite eye is covered.
Video 2. Video of a provider evaluating forstrabismus. This is a 7-year-old boy with esotropia whose inward-turnedeye refixates outward when his opposite eye is covered.
Download video file.(15M, MOV)
Ocular Motility and Nystagmus
In addition to alignment, ocular motility is animportant part of the eye examination. Parents who observe “funny eyemovements” may be the first observers of a complex strabismus syndrome,such as congenital fourth nerve palsy, Brown syndrome, or Duane syndrome.Congenital fourth nerve palsy is characterized by a vertical misalignment of theeyes caused by weakness of the ipsilateral superior oblique muscle. Childrentypically have a head tilt toward the side of the palsy. Brown syndrome is alsocharacterized by vertical misalignment of the eyes caused by a deficit of thesuperior oblique muscle where the affected eye cannot elevate in adduction.Duane syndrome is characterized by anomalous innervation of the lateral rectusby the sixth cranial nerve causing limitation in horizontal eye movements aswell as retraction of the globe on attempted adduction. If a patient has anesotropia, evaluating motility is important for determining the urgency of thereferral. The most common forms of esotropia, including congenital esotropia andaccommodative esotropia, typically have normal ocular motility. Limitation ofabduction (eye movement away from the nose) can be a sign of a sixth nerve palsyin contrast to congenital or accommodative esotropia with full ductions and noabduction limitation. In addition, the presence of nystagmus or unusual eyemovements in an infant or young child can indicate decreased vision orneurologic dysfunction and warrants further evaluation by either anophthalmologist or a neurologist.
Pupil Examination
The pupils should be equal in size and reactive to lightfrom birth. A dim room and using a bright light elicits the best pupil response,especially in newborns. The pupils normally will decrease in diameter withaccommodation and if the child is looking at the examiner at near; the pupilresponse may be less marked if the pupils are small already duringaccommodation. Any evidence of anisocoria or pupils of different shapes shouldbe referred to an ophthalmologist.
Instrument-Based Vision Screening
Provider-based visual acuity assessment depends on childparticipation and screener experience. With practice, instrument-based visionscreening can be fast and require less participation from the child. (Video 3) Instrument-based screening can be veryhelpful in screening children before reliable subjective visual acuity can beobtained. (9) Recent guidelines released bythe AAP in January 2016 recommend instrument-based screening starting at 1 year oldand continuing until the child can reliably read the eye chart. (10)
Video 3. Video of a technician using a visionscreener with a 6-year-old boy.
There are 2 types of instrument-based vision screening: photoscreeners andautorefractors. Neither type measures visual acuity itself but rather measures riskfactors for vision loss, including myopia, hyperopia, astigmatism, and strabismus.Children with retinal disease or structural causes for amblyopia may havefalse-negative screening tests. Amblyopia risk factors were identified in 5% ofpreschool children participating in 16 photoscreening programs of more than 400,000children. (11) Approximately 4% of childrenyounger than 6 years have myopia, 5% to 10% have astigmatism, and up to 20% havehyperopia. (12)(13)(14) Photoscreenersare binocular devices that estimate refractive error, media clarity, ocularalignment, and eyelid position. Photoscreeners have been shown to have highsensitivity and specificity when used in community and office settings. (15)(16)(17) Autorefractorsmonocularly estimate refractive error and are useful for screening for highrefractive error and anisometropia. Once a child is old enough to reliably read aneye chart, direct visual acuity should supplement vision screening. Instrument-basedvision screening would not detect structural abnormalities causing decreased vision(eg, retinal dystrophies or optic nerve hypoplasia) even if vision was poor becausevisual acuity is not directly measured. Table3 compares common commercially available instrument-based visionscreening devices.
Table 3.
Instrument-Based Vision Screening Devices (18)
| DEVICE | |||||
|---|---|---|---|---|---|
| iScreen (14) | Plusoptix S09, S12c (19) | Spot screener (12) | Righton Retinomax (4) | SureSight (20) | |
| Type | Photoscreener | Hybrid | Hybrid | Autorefractor | Autorefractor |
| Monocular/binocular | Binocular | Binocular | Binocular | Monocular | Monocular |
| Image interpretation | Vendor | Automated | Automated | Automated | Automated |
| Conditions screened | Refractive error, strabismus, anisometropia, anisocoria,cataracts | Refractive error, strabismus, anisometropia, anisocoria | Refractive error, strabismus, anisometropia, anisocoria | Refractive error | Refractive error |
| Cost per machine, $ | 4,200 | 7,595 | 7,490 | 12,495 | 3,999 |
| Cost per test | ∼$10 | None | None | None | |
| Time per test, seconds | 7 | 1 | 1 | 1 | 1 |
| Time for results | <1 h | Instant | Instant | Instant | Instant |
Open in a separate window
Data from Colburn J. Comparison of instrument-based visionscreening devices. American Academy of Ophthalmologywebsite.https://www.aao.org/pediatric-center-detail/vision-screening-performance-data-resource-2.Published 2014. Accessed August 1, 2017
Vision Screening Coding
Last, Current Procedural Terminology codes99173 and 99174 are specific for provider-based visual acuity screening andinstrument-based photoscreening, respectively. The AAP recommends that visionscreening not be bundled into the global code of well-child care. Adequatereimbursem*nt for photoscreening must be encouraged to promote widespread adoptionof vision screening. Unfortunately, some insurance plans may not cover visionservices. The National Eye Institute has information regarding vision servicesavailable to uninsured and underinsured children (https://nei.nih.gov/health/financialaid).
Summary
On the basis of expert consensus as well as prospective cohort research,routine vision screening decreases the incidence of vision loss in earlychildhood. (3)
Based on consensus, the most important aspects of a provider-based visionscreening are red reflex testing, external examination of lids andadnexa, ocular motility, and visual acuity testing.
Based on some research evidence as well as consensus, instrument-basedvision screening can be used to reliably evaluate vision in children.(10)
Referral to an eye care provider is indicated if a patient does not passa component of the vision screen or when further diagnostic andmanagement recommendations are required.
Footnotes
AUTHOR DISCLOSURE
Dr Loh has disclosed no financial relationships relevant to this article. DrChiang has disclosed that he has received research grants from the NationalInstitutes of Health and the National Science Foundation, that he is an unpaidmember of the Scientific Advisory Board of Clarity Medical Systems, and that heis a consultant/steering committee member of the RAINBOW study for Novartis.This commentary does not contain a discussion of an unapproved/investigative useof a commercial product/device.
References
1. Taylor D, Hoyt CS.Pediatric Ophthalmology and Strabismus.3rd ed.New York, NY:Elsevier Saunders;2005 [Google Scholar]
2. Couser NL, Smith-Marshall J.The Washington metropolitan pediatric visionscreening quality control assessment. ISRNOphthalmol.2011;2011:801957. [PMC free article] [PubMed] [Google Scholar]
3. de Koning HJ, Groenewoud JH, Lantau VK, et al.Effectiveness of screening for amblyopia andother eye disorders in a prospective birth cohort study.J Med Screen.2013;20(2):66–72 [PubMed] [Google Scholar]
4. Birch EE, Holmes JM.The clinical profile of amblyopia in childrenyounger than 3 years of age. J AAPOS.2010;14(6):494–497 [PMC free article] [PubMed] [Google Scholar]
5. American Academy of Ophthalmology PediatricOphthalmology/Strabismus Panel. Pediatric eyeevaluations; In: Preferred Practice Pattern®Guidelines. San Francisco, CA:American Academy of Ophthalmology;2012 [Google Scholar]
6. Committee on Practice and AmbulatoryMedicine, Section on Ophthalmology; American Association of CertifiedOrthoptists; American Association for PediatricOphthalmology and Strabismus; American Academy ofOphthalmology. Eye examination in infants, children,and young adults by pediatricians.Pediatrics.2003;111(4)(pt1):902–907 [PubMed] [Google Scholar]
7. Brodsky MC.Pediatric Neuro-ophthalmology.New York, NY: SpringerScience+Business Media; 2015 [Google Scholar]
8. Maguire MG; Vision in Preschoolers Study Group.Children unable to perform screening tests in Vision inPreschoolers Study: proportion with ocular conditions and impact on measuresof test accuracy. Invest Ophthalmol VisSci.2007;48(1):83–87 [PubMed] [Google Scholar]
9. Miller JM, Lessin HR; American Academy of Pediatrics Section onOphthalmology; Committee on Practice and AmbulatoryMedicine; American Academy of Ophthalmology;American Association for Pediatric Ophthalmology andStrabismus; American Association of CertifiedOrthoptists. Instrument-based pediatric visionscreening policy statement. Pediatrics.2012;130(5):983–986 [PubMed] [Google Scholar]
10. Donahue SP, Baker CN; Committee on Practice and Ambulatory Medicine, AmericanAcademy of Pediatrics; Section on Ophthalmology, AmericanAcademy of Pediatrics; American Association of CertifiedOrthoptists; American Association for PediatricOphthalmology and Strabismus; American Academy ofOphthalmology. Procedures for the evaluation of thevisual system by pediatricians. Pediatrics.2016;137(1).doi:10.1542/peds.2015-3597 [PubMed] [Google Scholar]
11. Donahue SP, Baker JD, Scott WE, et al.Lions Clubs International Foundation Core FourPhotoscreening: results from 17 programs and 400,000 preschoolchildren. J AAPOS.2006;10(1):44–48 [PubMed] [Google Scholar]
12. Giordano L, Friedman DS, Repka MX, et al.Prevalence of refractive error among preschoolchildren in an urban population: the Baltimore Pediatric Eye DiseaseStudy. Ophthalmology.2009;116(4):739–746,746.e1–4 [PMC free article] [PubMed] [Google Scholar]
13. Wen G, Tarczy-Hornoch K, McKean-Cowdin R, et al.; Multi-Ethnic Pediatric Eye Disease StudyGroup. Prevalence of myopia, hyperopia, and astigmatismin non-Hispanic white and Asian children: multi-ethnic pediatric eye diseasestudy. Ophthalmology.2013;120(10):2109–2116 [PMC free article] [PubMed] [Google Scholar]
14. Multi-Ethnic Pediatric Eye Disease StudyGroup. Prevalence of myopia and hyperopia in 6- to72-month-old African American and Hispanic children: the Multi-EthnicPediatric Eye Disease Study. Ophthalmology.2010;117(1):140-147.e3 [PMC free article] [PubMed] [Google Scholar]
15. Garry GA, Donahue SP.Validation of Spot screening device foramblyopia risk factors. J AAPOS.2014;18(5):476–480 [PubMed] [Google Scholar]
16. Matta NS, Singman EL, Silbert DI.Performance of the plusoptiX S04 photoscreenerfor the detection of amblyopia risk factors in children aged 3 to5. J AAPOS.2010;14(2):147–149 [PubMed] [Google Scholar]
17. Ransbarger KM, Dunbar JA, Choi SE, Khazaeni LM.Results of a community vision-screening programusing the Spot photoscreener. J AAPOS.2013;17(5):516–520 [PubMed] [Google Scholar]
18. Colburn JD.Comparison of instrument-based vision screeningdevices. American Academy of Ophthalmology website.https://www.aao.org/pediatric-center-detail/vision-screening-performance-data-resource-2.Published 2014. Accessed August 1, 2017
19. Plusoptix website. https://plusoptix.com/en/. Accessed August 1,2017.
20. SureSight® visionscreener. Welch Allyn website. https://www.welchallyn.com/content/welchallyn/americas/en/products/categories/physical-exam/eye-exam/vision-screeners/suresight_vision_screener.html.Accessed August 1, 2017
Articles from Pediatrics in Review are provided here courtesy of American Academy of Pediatrics
