The Causes and Consequences of the Diffusion of Precision Medicine: Evidence from Innovations in Breast Cancer Medicine - Project Summary/Abstract: Rapid advancements in DNA sequencing in the early 2000s paved the way for
precision medicine - an approach to tailor disease prevention and treatment while taking into account differences
in people’s genes, environments, and lifestyles. Today more than ten genetic tests enter the market every day,
ranging from tests that help predict drug response to tests that predict disease risk. Yet, relatively little is known
about the extent to which precision medicine has diffused into clinical practice and the consequences on the
healthcare system. The proposed project studies this question in the context of breast cancer, a diagnosis which
254,744 individuals received in 2018 alone, and for which multiple technologies have recently become available
to patients. One of the earliest precision medicine tools to reach the market was a genomic test that personalized
the decision to administer chemotherapy to a patient (OncotypeDX). While historically, the majority of women
with early-stage breast cancer would receive chemotherapy, with genomic-guided care, only women likely to
benefit from chemotherapy would receive it. Using Medicare as an example, the overall objective of the proposed
project is to understand the barriers to and facilitators of technological adoption by providers, and the
consequences of technological adoption on the healthcare system. To accomplish this, the proposed research
specifically aims to: (1) identify the effect of the introduction of OncotypeDX on provider practice patterns, patient
health, and healthcare spending, (2) explore the characteristics of adopting providers, and (3) explore the role
of financial incentives in provider technological adoption stemming from the 340B drug pricing program. Under
the first aim, a staggered difference-in-difference design will be used to estimate the causal impact of provider
technological adoption. For the second aim, key characteristics of provider technological adoption will be
identified as well as the determinants of under-adoption. Under the third aim, the role of financial incentives in
under-adoption will be estimated using variation stemming from the 340B program. The proposed project is
innovative because it is uses novel empirical designs to estimate the causal effect of technological adoption at
the population-level for an understudied class of technologies. The research proposed is significant because it
provides insight into the role of providers in the diffusion and impact of precision medicine on the healthcare
system, as well as the extent to which diffusion has been efficient and equitable. Identification of the determinants
of provider technological adoption may point to effective targets for information and education campaigns. The
proposed project aligns well with the Agency for Healthcare Research and Quality’s (AHRQ) research priority to
increase the affordability and efficiency of health care.
