Why cost effectiveness of treatment is useful to advocate for ROP services
Health economics can seem daunting at first sight, as the terminology used is different, and some of the concepts can be difficult to understand. However, in our everyday lives we constantly make large and small decisions where we either consciously or unconsciously weigh up two broad questions. These are ‘What will it cost me?’ in terms of time, money and effort and ‘What might I gain by this decision and what else might I not be able to do?’ in terms of experiences, friendships, learning, having enough food in the house or petrol in the car and so on.
Another question we constantly ask ourselves is ‘What is the best way to do this?’ There may be two ways. I could travel to visit a friend, for example. One would be to drive, which would be quicker, but I would have to pay for parking. The other way would be by public transport which would be slower, but cheaper.
Health economics asks similar questions as it focuses on how resources are best used in providing health care.
Why health economics is important
Health services are often constrained by lack of funding regardless of the context, and economic evaluations are used to identify the most efficient way of planning and allocating how these scarce resources are used among alternative activities. Put simply, economic evaluations compare two or more different interventions for their effectiveness (consequences) and their cost. Examples in relation to ROP might be to compare screening using indirect ophthalmoscopy with digital imaging, or comparing laser treatment with anti-VEGF treatment.
Measures used in economic evaluations
To undertake an economic evaluation, the cost is the sum of all the resources needed to deliver the intervention in monetary terms. Provider’s costs might include the cost of all the equipment and consumables, the salary contribution of staff and any travel costs, and the cost of using the space where the intervention is delivered. Some studies also include the costs of those receiving the intervention, such as travel costs, and time away from income generating activities. The effects, or consequences can be measured using disease-specific outcomes (such as more babies with ROP detected or successfully treated), or in monetary terms (the productivity gains of not being ROP blind for a life-time), or using health-related quality of life measures (such as better quality of life or less disability after treatment for ROP compared with no treatment).
Different types of economic evaluations
Cost minimisation, which identifies the cost saving of using an alternative intervention which has the same effectiveness as the initial intervention. For example, if screening using indirect ophthalmoscopy and digital imaging are equally effective in detecting sight-threatening ROP, a cost minimisation study would show which approach is cheaper to deliver, and hence be more efficient
Cost effectiveness, which uses health specific outcomes
Cost benefit analysis, which uses monetary outcomes
Cost utility analysis, which uses quality of life or other subjective outcomes.
The overall benefit of economic evaluations is that they can lead to decisions which can improve the quality of care and enhance efficiency.
Additional costs of an intervention
Another type of economic study identifies the additional cost of adding an intervention. There is a good example from Brazil, where the researchers estimated what the total cost of screening would be for all preterm infants at risk of ROP in government neonatal units across the country using indirect ophthalmoscopy and laser treatment. The overall cost included the costs of equipment for screening and treatment as well as equipment maintenance costs and for training. Salary costs were estimated for the ophthalmologists and for members of the neonatal team, and travel costs for the ophthalmologist. Data on the proportion of babies screened and the proportion treated were obtained from a study in six neonatal units. The costs and number to be screened and treated were then extrapolated across the whole country.
The estimated cost of ROP diagnosis and treatment for all at-risk infants was US$ 80 per infant. The additional cost to the health system for one year would be US$ 556,640 for a ROP program in 52% of the neonatal units in the country, which increased to US$ 856,320 for 80% coverage, and US$ 1.07 million for 100% coverage. Although this seems a lot of money, the startling finding was that the increase in funding needed to screen and treat all preterm infants at risk across the country was less than 1% of the total annual budget for neonatal care. This finding is a very important message to use in advocacy with policymakers.
Why is the economic argument that ‘systematic screening for ROP is cost effective’ so important for advocacy? Why is it not enough to suggest that the programme will prevent a child from going blind?
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