Methods of assessing the cost-effectiveness of caries preventive agents and procedures.

Before public finance is committed to a particular public health measure it is essential that the project should be analytically evaluated. Cost-benefit analysis is one method of choosing between alternative programmes. It suffers from the disadvantage that, while costs can be accurately assessed, the benefit to an individual of freedom from pain, discomfort or inconvenience cannot be simply expressed in monetary terms. Such benefits may therefore be omitted from calculations of cost-benefit and a programme with valuable indirect or intangible benefits may not receive adequate consideration in competition with other alternatives. Futhermore, since benefits may only accrue some time after expenditure has been incurred, inflation distorts the significance of cost-benefit calculations. Cost-effectiveness analysis is an alternative method which enables one to determine the least expensive of several alternative methods of achieving a stated objective. The application of these concepts to preventive programmes against dental caries is described. Distinction must be made between the effectiveness of preventive measures during controlled clinical trials on limited numbers of subjects and their value when applied under field conditions to the whole community. Detailed comparisons are made between various methods of the application of fluorides caries prevention by community fluoridation water supply, school water fluoridation and topical application of fluorides. It is concluded that while completely accurate and valid analyses of cost-effectiveness are not possible, they do enable dentistry to view its activities more objectively and to indentify the real issues which should affect future decisions.