Pitfalls in eye testing of children

Inadequate testing environment: Testing in a room with poor lighting or distractions can lead to inaccurate results.
Incorrect testing distance: Failing to maintain the appropriate testing distance can distort results and lead to false positives or negatives.
Incorrect choice of eye chart: Using a chart that is not age-appropriate or features unfamiliar symbols can result in unreliable outcomes.
Lack of cooperation: Children may not fully understand the testing process or may not cooperate, leading to inaccurate measurements.

Failure to correct for refractive errors: Not accounting for refractive errors such as nearsightedness or farsightedness can result in misdiagnosis or underestimation of vision impairment.
Inadequate testing of each eye independently: Screening each eye independently is crucial to identify unilateral vision problems that might otherwise go unnoticed.
Relying solely on screening tests: Screening tests should be followed up with comprehensive eye examinations by an eye care professional to confirm results and identify any underlying issues.

Two out of three children with poor vision are not detected during routine checks with the Danish eye chart from 1934.

Many young children have vision problems and should be wearing glasses, but these issues are not detected during tests, according to Politiken. Preschool children have their vision checked annually by a doctor, while school children are tested by a health nurse. Nevertheless, many children with impaired vision go undetected, as shown by a study involving nearly 500 children aged four to seven years.

A significant reason is that the most widely used eye chart in Denmark, the Østerberg chart from 1934, is not effective enough, according to Lisbeth Sandfeld, a senior doctor at Roskilde Hospital’s eye department. The Østerberg chart, which has a swan at the top, is no longer used in other countries. It only detects about half of the children with vision problems when used correctly, but in routine checks, only one in three children is detected.

A newer chart based on the LogMAR principle, on the other hand, can detect 85 percent of children with vision problems. This chart uses line drawings instead of filled symbols, making it easier for children with farsightedness to distinguish.

Poor vision can lead to concentration difficulties and learning challenges. The chairperson of the health nurses, Susanne Rank Lücke, urges municipalities to replace the Østerberg chart. The Danish Health Authority plans to change the guidelines and already recommends LogMAR charts to municipalities.