This analysis is performed from the third-party insurer perspective, meaning that only direct medical costs and outcomes are considered. Although it excludes a number of societal costs and benefits, this third-party perspective is widely used throughout the ophthalmic literature because there is no consensus about which societal factors to include.27,28,38,46 In a telemedicine strategy, benefits to ophthalmologists might include decreased travel, opportunity cost savings, and qualitative matters such as satisfaction. Images could also be used for secondary purposes such as teaching, research, and improved clinical care through comparison with prior photographs. These factors are not relevant to direct medical spending because they are not generally reimbursed, and they are therefore excluded from our analysis. However, we note that they may favor telemedicine. Also, study costs were derived from Medicare reimbursement values because this standardized payment system is a reasonable proxy for costs and allows for comparison with most studies in the ophthalmic literature.27,28 We emphasize that this is the accepted method for performing health care cost-effectiveness analysis27- 29,38,45,46 but acknowledge that these Medicare charges may not capture the true cost of ROP management. For example, some physicians negotiate retainer fees from hospitals in addition to receiving third-party payments for ophthalmoscopic examinations. If this factor were considered, it might further favor the telemedicine strategy. Moreover, the costs of telemedicine imaging devices and the salaries of personnel operating them are excluded from this analysis. In standard cost-utility analysis, it is assumed that these latter costs are recovered through technical fees associated with procedures. Finally, in cost-utility analysis, the ramifications of infants incorrectly untreated by telemedicine or ophthalmoscopy are considered to be fully represented by the decreased utility outcome in that group (Table 2). Specifically, this study is not intended to quantify the financial effect of medicolegal liability, and it is not necessarily clear which strategy would be more affected in these situations. In a telemedicine strategy, the availability of photographic documentation could protect physicians from liability or could increase medicolegal risk by subjecting images to heavy scrutiny. A related study examined the cost-effectiveness of photographic ROP screening in the United Kingdom from a societal perspective, with mixed results depending on the approach used.24 Further studies may elucidate the cost-benefit effect of these societal factors.