how robustly positive such ratios are will depend on the same range of assumptions and estimates that we encountered above.

And despite undoubted benefits to resistant school construction, for example, it is worth comparing the cost of resistant construction to school budgets in developing countries. If school retrofit/earthquake proof construction comes at the cost of building fewer schools and excluding girls and boys from education, the long-term health effects of such construction may even be negative (See Box 9). It is worth noting that even while as many as 2,500 children worldwide die each year in school collapse, more than 10,000,000 children under the age of five die each year from other causes before they can even make it to school – and the majority of those deaths can be easily and cheaply prevented. In areas of very high risk of earthquake, where cheap engineering solutions are available, the benefit to cost ratio of such projects can look very good. If the risk of earthquake is lower, or costs higher, retrofit in particular may look less attractive than other methods of improving child health. This is particularly the case where overall levels of child health are poor, and particularly in cases where earthquake proofing will come at the expense of additional school construction and the exclusion of children from educational opportunities.

A more detailed analysis based on school retrofit in Istanbul suggested that the program would make sense at a value of $400,000 per life saved.<sup>23</sup> Compare this number to education expenditures in poor countries. ‘Discretionary’ expenditure – money left over after paying teachers’ salaries used to cover supplies, teaching equipment, utility bills, building maintenance and construction—is as low as $5 per year per primary student per year in many countries (Grace and Kenny, 2003). If the average school size is 100 children, this suggests retrofitting alone would be equal to 16 years of a school’s total discretionary expenditure in many poor countries. This expenditure will actually benefit only some small proportion of the schools which embark on it (in preventing collapse that otherwise would have occurred).

Perhaps more to the point, it is worth comparing the costs of improved school building safety to a number of other efforts to improve health outcomes in developing countries – which we have seen may save lives at far lower costs. When we add in the relative simplicity of the health interventions compared to the complex engineering often required for retrofit, likely benefits appear to skew ever more heavily to health expenditures over retrofitting. As noted in some cost benefit studies of the value of retrofitting projects, it is not uncommon to find that existing construction is substandard and quality control of building materials was limited (Smyth et. al. 2004a). These same problems will reduce the effectiveness of retrofitting projects, thereby (and perhaps severely) reducing benefitcost ratios.

> 23 This exercise by Smyth et. al. (2004a) suggests retrofit costs between $8-20,000, the loss of fifteen lives in the event of collapse, a replacement cost of $160,000 and a value of a statistical life of $400,000.  Using a 3% discount rate, assuming that schools are occupied one third of the time (apparently not allowing for holidays and weekends) and earthquake risk calculated for Istanbul, the estimate produces strongly positive net present values.  For reasons discussed in the text, some of these estimates and assumptions may be more favorable than justified.  Nonetheless, this analysis does suggest that in higher-risk areas such as Istanbul, school retrofitting projects may be justifiable.

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