Methods: In a prospective randomised controlled trial, compliance was measured for one week every three months during 30 months in newly diagnosed amblyopic children in The Hague, Frankfurt and Leicester. The family’s social-economic and ethnic background was assessed through a questionnaire. Children were randomised to receive either an educational cartoon story explaining, without text, the rationale for treatment to the child with reward stickers and an information sheet, or a picture to colour. All received standard orthoptic care by a treating orthoptist, who was unaware of the randomisation. The electronic device and educational programme were distributed via home-visits by researchers. The primary outcome measure was percentage of compliance (realised/prescribed occlusion time). The secondary outcome measure was influence of social-economic, ethnic and clinical factors on compliance.