Issues in the economic evaluation of community water fluoridation.

Community water fluoridation has long been recognized as an effective public health intervention in the prevention of dental caries. The recently documented secular decline in dental caries, however, presents for policy makers the challenge of appropriately allocating limited health care resources between a variety of health care programs. Appropriate economic assessment of these alternatives becomes critical for rational distribution of such resources. Cost-benefit and cost-effectiveness analyses are techniques that, when used correctly, can guide policy makers facing such decisions. This paper reviews and critiques the published literature assessing the cost effectiveness and cost benefit of community water fluoridation using criteria developed for economic evaluation. Eight papers met the criteria for inclusion in the present study. In general, the articles failed to incorporate the declining prevalence of dental caries into their analyses and to fully document costs associated with water fluoridation. Treatment savings from dental care averted secondary to water fluoridation were not appropriately incorporated into the cost-effectiveness analyses, thereby overestimating the marginal cost associated with fluoridation. Specification of outcome measures to assess the consequences of water fluoridation failed to incorporate the dynamic nature of dental disease. Suggestions for improving the generalizability and usefulness of future cost-benefit and cost-effectiveness analyses are made.