Screening children who are already under the care of an optician may not be necessary as most opticians operate a re-call system for regularly checking sight of their patient. However, if you have concerns and would like to check the vision of a child who normally wears glasses, it is important that children wear the same glasses as they do every day. In this case the test will indicate whether they have any vision problems with the glasses on. When you are conducting the screening, just ask the children to cover the appropriate eye, as the occluding glasses are not suitable for this.