Economic Valuation of Selected Illnesses in Environmental Public Health Tracking.

BACKGROUND

In benefit-cost analysis of public health programs, health outcomes need to be assigned monetary values so that different health endpoints can be compared and improvement in health can be compared with cost of the program. There are 2 major approaches for estimating economic value of illnesses: willingness to pay (WTP) and cost of illness (COI). In this study, we compared these 2 approaches and summarized valuation estimates for 3 health endpoints included in the Centers for Disease Control and Prevention's National Environmental Public Health Tracking Network-asthma, carbon monoxide (CO) poisoning, and lead poisoning.

METHOD

First, we compared results of WTP and COI estimates reported in the peer-reviewed literature when these 2 methods were applied to the same study participants. Second, we reviewed the availability and summarized valuations using these 2 approaches for 3 health endpoints.

RESULT

For the same study participants, WTP estimates in the literature were higher than COI estimates for minor and moderate cases. For more severe cases, with substantial portion of the costs paid by the third party, COI could exceed WTP. Annual medical cost of asthma based on COI approach ranged from $800 to $3300 and indirect costs ranged from $90 to $1700. WTP to have no asthma symptoms ranged from $580 to $4200 annually. We found no studies estimating WTP to avoid CO or lead poisoning. Cost of a CO poisoning hospitalization ranged from $14 000 to $17 000. For patients who sustained long-term cognitive sequela, lifetime earnings and quality-of-life losses can significantly exceed hospitalization costs. For lead poisoning, most studies focused on lead exposure and cognitive ability, and its impact on lifetime earnings.

CONCLUSION

For asthma, more WTP studies are needed, particularly studies designed for conditions that involve third-party payers. For CO poisoning and lead poisoning, WTP studies need to be conducted so that more comprehensive economic valuation estimates can be provided. When COI estimates are used alone, it should be clearly stated that COI does not fully capture the nonmarket cost of illness, such as pain and suffering, which highlights the need for WTP estimates.