Evaluation of diagnostic procedures: A review of the issues

Abstract The expensive proliferation of new diagnostic medical technologies necessitates their rigorous evaluation. Diagnosis seeks to improve health outcomes by providing better information to guide treatment decisions. Evaluation may focus on various links in the management of patients by investigating (1) how diagnostic technologies affect the the information available to the physician, (2) how improved Information affects treatment decisions, and (3) how altered treatment decision affect health outcomes. For diagnostic procedures that do improve health outcomes, the gain in health status should be weighed against potential cost increases. This comparison may be made using risk-benefit and cost-effectiveness analyses. Experience in evaluating diagnostic technologies has shown the importance of (1) estimating effect size, (2) randomizing, (3) blinding, (4) enhancing external validity, (5) accounting for patient characteristics, and (6) reflecting patient values. Errors in adopting new diagnostic procedures may be reduced through better coordination of development, evaluation, and dissemination. This requires (1) improved evaluative decision making, (2) restraint among potential users, and (3) accelerated evaluation.