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Scottish Pre-School Vision Screening - First 3 Years of National Data
1Ninewells Hospital, NHS Tayside, GB.
Insights
The Pre-school Orthoptic Vision Screening (POVS) in Scotland achieved 85.5% coverage, effectively detecting visual problems like amblyopia in young children. The program demonstrated high sensitivity with a true positive rate of 88.9%.
Area of Science:
- Ophthalmology
- Public Health
- Pediatrics
Background:
- The Scottish government implemented Pre-school Orthoptic Vision Screening (POVS) for early detection of visual issues in children.
- Target conditions include amblyopia, refractive errors, and strabismus.
- This study presents preliminary findings from the first three years of the POVS program.
Purpose of the Study:
- To evaluate the effectiveness of the POVS program in Scotland.
- To report on coverage, referral rates, and accuracy of the screening.
- To assess the program's sensitivity in identifying visual problems in pre-school children.
Main Methods:
- Retrospective data collection from Scottish health boards (2013-2016).
- Analysis of screening coverage, referral rates, true positives, and positive predictive values.
- Exclusion of children who opted out (1.8%) or already attended hospital eye services (3.1%).
Main Results:
- Screening covered 167,962 children, with a mean coverage of 85.5% across health boards.
- The mean referral rate was 17.9%.
- High accuracy was observed with a mean true positive rate of 88.9% and a positive predictive value of 86.9%.
Conclusions:
- The POVS program in Scotland demonstrates excellent mean coverage.
- Consistently high true positive rates confirm the program's sensitivity for detecting visual problems.
- The findings support the value of standardized vision screening in pre-school children.
Introduction:
Pre-school orthoptic vision screening (POVS) was implemented by the Scottish government and is a standardised assessment to promote early detection of visual problems in children. The target conditions are amblyopia, refractive errors and strabismus. We present the preliminary findings for the first three years of the screening program.
Methods:
The data from POVS was collected retrospectively. The data includes screening years 2013 to 2016 inclusive. Data was collected from each health board in Scotland. We report the coverage, referral rate, true positives and positive predictive values.
Results:
A total of 167,962 children were due to have vision screening over the 3 screening years included in this paper. This figure does not include the children that opted out of the eye test (mean opt-out rate 1.8%) and children that already attend the hospital eye service (mean already attend rate 3.1%). The POVS program had a mean coverage of 85.5%, ranging from 63.7% to 94.8% between health boards. Over the 3 year screening period, the mean referral rate was found to be 17.9%. The mean true positive rate was 88.9%, and the mean positive predictive value was 86.9%.
Conclusion:
The Scottish data set on pre-school orthoptic vision screening has shown excellent mean coverage. A consistently high true positive rate over the three screening years demonstrates it is a sensitive screening program, which is essential for the detection of visual problems in children.
