PhD defence F. (Frea) Sloot

To examine how many cases of amblyopia (lazy eye) are detected at Child Healthcare Centers in the Netherlands at 6-24 months of age the Optimisation of Amblyopia Screening study (OVAS) assessed whether the omission of orthoptic vision screening tests between age 6-24 months would impact the frequency, severity and age of detection of amblyopia. In this study two sequential birth cohorts, with and without vision screening, were followed up from six to 45 months of age. Strabismus (squint) amblyopia and visually apparent eye disorders were mainly detected by the parents before the age visual acuity could be measured and were detected regardless of formal vision screening. Omission of routine preverbal eye screening tests between the age of 6-24 months in the Netherlands did not lead to significant differences in amount of children referred, in total number of cases of amblyopia detected or in the severity of the detected amblyopia. Refractive amblyopia (difference in strength of glasses) was, almost exclusively, detected with the visual acuity measurements between 36-60 months. The visual acuity measurements with the Amsterdam Picture Chart at age 36 months often failed. Inspired by the success of the disinvestment study of selected parts of the screening we initiated a pan-European comparison of vision screening programmes in all countries in Europe. This comparison showed that vision screening programmes are very divers. A implementation study for visual acuity measurement was started in Romania.

The PhD defences do not take place publicly in the usual way in the Senate Hall at campus Woudestein or in the Professor Andries Querido Room at the Erasmus MC. The candidates will defend their dissertation either in a small group or online.