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Dr Newsham's effort to inform parents of children with amblyopia about occlusion therapy is laudable but incomplete. Ethical considerations of informed consent require full disclosure of all aspect of the proposed treatment. In the current instance this compels inclusion of the following points:
1. Occlusion therapy has never been scientifically validated with a randomized, controlled study.
2. The dose / response relationship has never been defined. Flynn et al. stated that 'Success was not related to the duration of occlusion therapy, type of occlusion used'.  The variety of treatment protocols accentuate another dilemma 'owing to our paucity of knowledge on the dose-effect relation - a situation one finds hard to imagine for any
comparably established therapy outside ophthalmology. In other words we have no understanding of the dose-effect relation of occlusion in amblyopia therapy'. 
3.The application of 'greater levels of occlusion being prescribed for more severe amblyopia is
compromised by the observation 'that success was related to the depth of visual loss before treatment'.
4. The benefits of treatment are likely to deteriorate following cessation of patching. 
5. Visual acuity normally improves as children become more mature, literate, and familiar with vision testing protocols. 
This is also true for amblyopic eyes. In amblyopic children between 3 and 7 years old without treatment visual acuity was
shown to consistently improve in each older age group. 
6. Both the occluded and the amblyopic eyes improve at the same rate during treatment. 
7. Success in amblyopia treatment is usually defined as improvement by a minimum of three lines. Many of the successfully treated patients, by that criterion, will still not have normal vision at the end of presumably successful treatment. One quarter of treated patients with initial acuity better than 20/100 do not even achieve these limited goals. The comments about achieving normal vision may raise expectations that will not be achieved.
Moreover, it is not clear that performance on reading an eyechart is a complete indicator of visual function. Acuity
improvement with occlusion may not be accompanied by improved performance on the other tests - such as vernier acuity
or contrast sensitivity. 
8. Occlusion therapy does have potential adverse effects beyond disruption of family and social life  and interference with
9.Despite decades of occlusion therapy the prevalence of amblyopia in the adult population is similar to that of the school-age population.  Moreover, 'the prevalence of unilateral amblyopia was not found to be statistically different by age group'.  This suggests that long term benefits of conventional therapy are not demonstrated in demographic studies.
Patients and their families should be provided with comprehensive information concerning proposed treatments in order to make appropriate judgements. Physicians are obliged to make this information accurate and inclusive.
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compliance in patching for amblyopia. Strabismus 1999 Jun;7(2):113-23.
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(8) Dorey SE, Adams GG, Lee JP, Sloper JJ. Intensive occlusion therapy for amblyopia. Br J Ophthalmol 2001 Mar;85(3):310-3.
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