Public Health Intervention− Impacts and Behavioral Responses

This paper evaluates the impacts of and behavioral responses to cost-sharing in population-based public cancer screening, one of the most common public health interventions, using Korea's National Cancer Screening Program (NCSP). It provides free stomach and breast cancer screenings to those below the insurance contribution cutoff, and 50% copayment were charged to those above. Free cancer screening substantially increases the cancer screening take up rate, yielding more cancer detections. Nevertheless, the program was unsuccessful along other key dimensions. First, the initial increase in cancer detections was quickly crowded out by the decrease in cancer detections through other channels, such as private screening and diagnostic testing. Second, those who were induced to take up cancer screening by the cash incentive (compliers) were relatively healthy. These compliers' baseline cancer prevalence is as high as those who take up screening regardless of the availability of free cancer screening (always takers). Those who do not undergo screening regardless of the availability of free cancer screening (never takers) had the highest cancer mortalities, and thus stood to benefit the most from the screening they did not receive. Taken together, free public cancer screening has a limited impact on cancer- and all-cause mortalities. This analysis demonstrates that even when take up is significantly responsive, population based cancer screening can be ineffective. More broadly, our study suggests that the impact of health and social intervention programs, even when they display large participation responses, crucially depend upon the potential behavioral responses of the agents involved. (JEL: I10, H40)