Economic evaluation of different methods of screening for amblyopia in kindergarten.
OBJECTIVE
To compare the cost-effectiveness of 5 methods of screening for untreated amblyopia in kindergarten from a third-party-payer perspective: A) uncorrected monocular visual acuity testing with pass threshold > or =0.5 (20/40) and < or =1 line difference between eyes; B) same as A, but pass threshold > or =0.6 (20/32); C) same as A, plus cover tests and examination of eye motility and head posture; D) same as C, but pass threshold > or =0.6 (20/32); and E) refractive screening without cycloplegia using the Nikon Retinomax autorefractor.


METHODS
A decision-analytic model was used with a time horizon until diagnostic examination. According to the model, all 3-year-old children were screened in kindergarten with 1 of the screening methods. Children with positive screening results were referred to an ophthalmologist for diagnostic examination. Children with inconclusive screening results were either referred to an ophthalmologist directly (option 1) or rescreened by the same method after 1 year and referred to an ophthalmologist if rescreening was positive or inconclusive (option 2). Screening test characteristics and costs were estimated on the basis of a field study in which 1180 3-year-old children were examined by orthoptists in 121 German kindergartens.


RESULTS
Compared with methods A option 1 (A-1), B-1, C-1, C-2, E-1, and E-2, there was at least 1 other method that was both less costly and more effective. The average costs per detected case were lowest for method A-2 (878 Euro), followed by methods B-2 (886 Euro), D-2 (908 Euro), and D-1 (965 Euro). When these methods were compared with each other, the additional costs per extra case detected were 1058 Euro (B-2 vs A-2), 1359 Euro (D-2 vs B-2), and 13 448 Euro (D-1 vs D-2).


CONCLUSIONS
Monocular visual acuity screening with rescreening of inconclusive results had a favorable cost-effectiveness. By adding additional test items, few more cases could be detected. Because of a great proportion of false-negative, false-positive, and inconclusive results, refractive screening was less effective with an unfavorable cost-effectiveness.
König
Hans-Helmut
HH
Department of Health Economics, University of Ulm, Ulm, Germany. hans-helmut.koenig@mathematik.uni-ulm.de
Barry
Jean-Cyriaque
JC
D000550:Amblyopia / Q000175:diagnosis* / Q000517:prevention & control; D002675:Child, Preschool; D003362:Cost-Benefit Analysis; D003661:Decision Support Techniques; D003941:Diagnostic Techniques, Ophthalmological / Q000191:economics; D005133:Eye Movements; D005858:Germany; D017048:Health Care Costs; D006801:Humans; D007349:Insurance, Health, Reimbursement; D011237:Predictive Value of Tests; D012017:Referral and Consultation; D012572:School Health Services / Q000191:economics; D012680:Sensitivity and Specificity; D015351:Vision Screening / Q000191:economics*; D014787:Vision Tests / Q000191:economics; D014792:Visual Acuity