Increasing prevalence of stereopsis screenings

Over the past few decades, the increasing number of ophthalmologists who specialise in children's vision problems, as well as orthoptists who are often responsible for ensuring that they are performed correctly, has contributed significantly to the spread of stereopsis screening in children.

Their international umbrella organisations are the WSPOS (World Society of Pediatric Ophthalmogists) and the IOA (International Association of Orthoptics).

The problem with the introduction of photoscreening

In some countries, apparative screening with so-called photoscreening has become established in recent years. Although refractive media such as lens opacities, reduced visual acuity and retinas can be reliably examined from infancy onwards, small-angle strabismus up to 5 degrees (microstrabismus), which can also lead to unilateral amblyopia, is not detected by these screenings.

For this reason, most experts consider photo-screening alone to be insufficient and recommend that young children undergo a separate stereotest early on and several times during their development.

List of countries without stereopsis screening

In the countries included in this listing with the note "*no stereopsis screening", stereopsis is not routinely screened, i.e. neither the Lang stereopsis test nor other star tests are used in vision screening. Only the Brückner test or Hirschberg test are mentioned, which test the position of the eye axes alone, but not stereopsis.

• England and Wales: from the fourth to the end of the seventh year of life: by orthoptist, specialist nurse or health care assistant: no stereo vision test* - download (PDF) In a population-based cohort study of children, data were available for 7825 seven-year-old children. Of these, 2.3% (95% CI 2.0% to 2.7%) had manifest strabismus, 3.6% (95% CI 3.3% to 4.1%) had past/present amblyopia and 4.8% (95% CI 4.4% to 5.3%) were hypermetropic (Williams et al., 2008)
• Netherlands: from the fourth to the end of the seventh year of life: by paediatric nurses and paediatricians: no stereotest* - Download (PDF) *de Koning et al. (2013) investigated the effectiveness of screening for amblyopia and other eye disorders in a prospective 7-year birth cohort study (n=4,624) using the same data set as the study by Groenewoud (2010) mentioned earlier. They report: The sensitivity of the Dutch vision screening programme was 73% at age 7 years. The specificity of the Dutch vision screening programme was 83% at age 7 years. The prevalence of treated or untreated amblyopia between birth and 6 years of age was 3.4% in a 7-year birth cohort study of 4,624 children (Groenewoud 2010).
• Denmark: from the fourth to the end of the seventh year of life: by general practitioner and public health nurse: no stereotest.* - Download (PDF) *The prevalence of strabismus is reported to be 2.56% at 7 years of age, according to a dissertation by Torp-Pedersen (2017) based on Danish National Health Records. The percentage of children treated for strabismus and amblyopia after being screened before the age of 7 is 8-10% (Torp-Pedersen, 2017). Specific data on strabismus and amblyopia are not publicly available without seeking permission. There is no centrally registered documentation of who has received screening, as most screening is done in private eye care practices. These professionals do not submit data to databases, so it is not possible to screen these children.
• Sweden: Ophthalmologists, paediatricians, general practitioners (GP) or specialised nurses at schools, hospitals, health centres: no stereotesting.* - Download (PDF)
• Norway: from age 4 to 7, general practitioners, health nurse: no stereotest* - Download (PDF)
• Finland: from age 4 to 7, GPs, public health nurses: no stereotest* - download (PDF)
• Czech Republic: from age 4 to 7, paediatricians, public health nurses: no stereotest* - Download (PDF)
• Slovakia: from age 4 to age 7: paediatricians: no stereotest* - Download (PDF) The prevalence of treated or untreated and persistent amblyopia at age 7 is estimated at 20%.
• Poland: from age 4 to 7 years, by general practitioners(GP), ophthalmologists, paediatricians and nurses: no stereotest*. - Download (PDF) The prevalence of treated or untreated amblyopia in Poland at age 7 years is estimated to be 3%, and the prevalence of persistent amblyopia (missed or untreated at screening) is estimated to be 1% at age 7 years. The prevalence of strabismus at age 7 years is estimated at 5%.
• Bulgaria: between birth and 3 years of age, by neonatologist, then by general practitioner, but only visual acuity. No stereo test*. - Download (PDF) A cross-sectional study (Dikova, Dragoev and Chernodrinska, 2018) of 1675 children in western Bulgaria aged 4-10 years found that the prevalence of treated or untreated amblyopia in Bulgaria at age 7 years is estimated at 2.5%. However, as there is no standardised screening in Bulgaria, it is not possible to determine the prevalence of persistent amblyopia. No data are available on the prevalence of strabismus in Bulgaria.
• Greece: from the age of four to 7 years, by paediatricians, ophthalmologists, general practitioners. No stereotest*. - Download (PDF) Prevalence/diagnosis of strabismus and amblyopia: No data available
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• Romania: from the age of four to 7 years, by ophthalmologists in kindergarten. No stereotest*. - Download (PDF) No data are available on the prevalence of strabismus or amblyopia in children aged up to 7 years.
• Israel: from age 4 to 7 years, by optometrists, public health nurses, trained lay people, No stereotest*. - Download (PDF) No data are available on the prevalence of treated or untreated amblyopia at age 7 years.
• Estonia: from age 4 to 7 years, by outpatient clinic, No stereotest*. - Download (PDF)
• Croatia: from the age of four to 7, by ophthalmologist at child health centre. No stereotest*. - Download (PDF) The prevalence of treated or untreated amblyopia in Croatia is estimated at 8.08% at 48-54 months of age, based on the assessment of 15,648 children.
• Ireland: from age four to age 7, by public health nurse, public health officer. No stereotest*. - Download (PDF) No data on prevalence of amblyopia or strabismus
• Turkey: from age four to age 7, by paediatrician, ophthalmologist, public health nurse. No stereotest*. - Download (PDF) In Turkey, the prevalence of treated or untreated amblyopia is estimated to be 3-4%, with a prevalence of persistent amblyopia (missed at screening or not treated by age 7 years) of 0.02%. Further data are not available.
• Northern Macedonia: from age four to age seven, by ophthalmologist, at university clinic. No stereotest* - download (PDF) No data are available on the prevalence of treated or untreated amblyopia, persistent amblyopia or strabismus.
• Montenegro: from four to seven years of age, by paediatrician in practice. No stereotest*. - Download (PDF) There is no information on the prevalence and diagnosis of visual impairment in children up to 7 years of age.
• Albania: from age four to seven years, by paediatrician or ophthalmologist in outpatient clinic. No stereotest*. - Download (PDF) No information is available on the prevalence and diagnosis of visual disorders in children up to 7 years of age.