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Published on: July 9, 2016
Semistructured Observation of Population-based Eye Screening in The Netherlands
Frea Sloot1, Aya Sami1,2, Hatice Karaman1,2
1a Department of Ophthalmology , Erasmus University Medical Centre, Rotterdam , the Netherlands.
Insights
Youth healthcare physicians in the Netherlands often perform vision screening tests inadequately, particularly cover-uncover and alternating-cover tests. While some tests like Hirschberg and fundus red reflex are done well, others need improvement for better child vision screening.
Area of Science:
- Ophthalmology
- Pediatrics
- Public Health
Background:
- Youth healthcare (YHC) physicians in the Netherlands conduct routine vision screenings for children aged 1-60 months.
- These screenings include various tests such as fundus red reflex, Hirschberg test, and visual acuity (VA).
Purpose of the Study:
- To assess the performance and adherence to guidelines of vision screening tests conducted by YHC physicians.
- Identify areas of strength and weakness in current vision screening practices.
Main Methods:
- Semistructured observations of 23 YHC physicians examining 329 children.
- Observation forms developed by orthoptic students, with training provided by experts.
- Assessment criteria based on the Dutch Child Vision Screening Guideline and Manual for Orthoptic Examination.
Main Results:
- High performance rates for Hirschberg test (88%), fundus red reflex (89%), and visual acuity (VA) measurement (94% in eligible age group).
- Inadequate performance for cover-uncover test (48% correct), alternating-cover test (36% correct), and eye motility tests (7% correct).
- Pupillary reflexes were performed in only 14% of cases, often due to inability to dim room lights.
Conclusions:
- While Hirschberg test, fundus red reflex, and VA are generally performed adequately, significant deficiencies exist in the execution of cover-uncover and alternating-cover tests, and eye motility assessments.
- Improvements are needed in the consistent and correct application of all vision screening components to ensure effective early detection of visual impairments in children.
Background:
In the Netherlands, youth-healthcare (YHC) physicians screen children 7 times for vision disorders between the ages of 1 and 60 months. Examination consists of inspection of the external structures of the eye, fundus red reflex, Hirschberg test, pupillary reflexes, cover-uncover test, alternating-cover test, eye motility, monocular pursuit, and, from 36 months onwards, visual acuity (VA). We observed how well these tests are done.
Methods:
Screening test performance was assessed with semistructured observations. Two orthoptic students developed a semistructured observation form. In addition to extensive instructions from an orthoptist and YHC-physicians instructor, they attended 2 one-day courses for YHC physicians. Tests were assessed using criteria based on the Dutch Child Vision Screening Guideline version 2010 and the Dutch Manual for Orthoptic Examination. Type of chart, testing distance, and starting eye were recorded for VA measurements. The observations in the first week were done simultaneously by the two observers and checked for concordance.
Results:
Concordance between the two observers was good. Twenty-five YHC physicians were observed during 100 days in total. Two physicians were excluded because they examined few children. The remaining 23 physicians examined 329 children, of whom 82 were aged 1-4 months, 157 aged 6-24 months, and 90 aged 36-45 months of age. Fundus red reflex was performed in 89% of children, Hirschberg test in 88%, pupillary reflexes in 14%, cover-uncover test in 65%, alternating-cover test in 62%, eye motility in 68%, monocular pursuit in 23%, and VA at 36-45 months in 94%. Forty-eight percent of cover-uncover tests, 36% of alternating-cover tests, and 7% of eye motility tests were performed correctly. VA was measured at 3 meters in 2%, others at 5 meters in accordance with the guideline. A picture chart was used instead of the Landolt-C at the age of 45 months in 23%. VA measurements were performed correctly in 89%, fundus red reflex in 89%, and Hirschberg test in 87%.
Conclusion:
Hirschberg test, fundus red reflex, and VA were adequately tested in most cases. Cover-uncover test, alternating-cover test, and eye motility were often performed inadequately. Pupillary reflexes were skipped often as room lights could not be dimmed.
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