Estimating the Impact of Medical Innovation: A Case Study of HIV Antiretroviral Treatments

Working Paper: NBER ID: w11109

Authors: Mark G. Duggan; William N. Evans

Abstract: As health care consumes a growing share of national income in the U.S., the demand for better estimates regarding both the benefits and the costs of new health care treatments is likely to increase. Estimating these effects with observational data is difficult given the endogeneity of treatment decisions. But because the random assignment clinical trials (RACTs) used in the FDA's approval process do not consider costs, there is often no good alternative. In this study we use administrative data from the Medicaid program to estimate the impact of a particular category of new treatments - HIV antiretroviral drugs - on health care spending and health outcomes. We use the detailed information on health care utilization to proxy for health status and exploit the differential take-up of ARVs following their FDA approval. Our estimate of a 70 percent reduction in mortality is in line with the results from RACTs and with studies that had more detailed clinical data. We also find that the ARVs lowered short-term health care spending by reducing expenditures on other categories of medical care. Combining these two effects we estimate the cost per life year saved at $22,000. Our results suggest that the administrative data that is readily available from programs like Medicaid, used with a properly specified econometric model that allows for heterogeneity in take-up rates and in effectiveness based on initial health conditions, can produce reliable estimates of the impact of new health care treatments on both spending and health.

Keywords: HIV; Antiretroviral Treatments; Health Care Spending; Mortality; Medicaid

JEL Codes: H51; I12; I18


Causal Claims Network Graph

Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.


Causal Claims

CauseEffect
HIV antiretroviral treatments (ARVs) (Q16)reduction in mortality rates (I14)
ARVs (Q16)lower short-term health care spending (H51)
ARVs (Q16)increased pharmaceutical spending (H51)
ARVs (Q16)decreased need for hospitalizations (I19)
ARVs (Q16)improved health outcomes (I14)
reduced mortality and lower overall health care spending (H51)cost per life year saved (J17)

Back to index