Dissertation Title: "On the Value of Biomedical Research and Medical Care"This dissertation consists of three chapters that investigate the value of biomedical research and medical care.
Chapter 1 studies trends in biomedical research methods and reporting over 25 years and identifies factors associated with biomedical research quality. A comprehensive database on biomedical research quality, combining systematic expert assessment of randomized controlled trial (RCT) methods with bibliometric and funding information in a sample of 20,571 RCTs is assembled using web-scraping and text-mining. Time series describes the proportion of RCTs using adequate methods, inadequate methods and poor reporting. A multinomial logit model tests potential factors associated with methods and reporting, including funding source, first author affiliation, clinical trial registration status, study novelty, team characteristics, technology and geography. 59.3% of RCTs used inadequate methods (N=12 190) and 35.0% were poorly reported (N=7208). The proportion of poorly reported RCTs decreased from 42.5% in 1990 to 30.2% in 2015. The proportion of RCTs using inadequate methods increased from 54.9% in 1990 to 59.5% in 2015. Industry funding, top pharmaceutical company affiliation, trial registration, larger authorship teams, international teams and drug trials were associated with a greater likelihood of using adequate methods. National Institutes of Health funding and university prestige were not. Even though reporting has improved since 1990, the proportion of RCTs using inadequate methods is high (59.3%) and increasing, potentially slowing progress and contributing to the reproducibility crisis. Stronger incentives for the use of adequate methods are needed.
Chapter 2 studies incentives for the use of adequate methods in biomedical research. Specifically, this chapter investigates how the adequacy of methods affect experimental results and publication outcomes of randomized controlled trials (RCTs). RCTs inform medical practice, health care delivery, follow-on research, regulation, and health policy. Yet, many RCTs are inadequately randomized, blinded, and reported. To analyze scientists' and firms' incentives to meet clinical trial standards, I assemble a detailed database on research methods, experimental results, bibliometric information, and funding for 23,321 RCTs published between 1990 and 2018. I estimate the impact of meeting scientific standards on three outcomes: (1) the direction and significance of experimental results; (2) the impact factor of the publishing journal; and (3) the number of citations the publication receives. I find that increasing numbers of inadequacies increase the probability of finding support for product adoption by 7% per inadequacy, but decrease journal prestige and citations. Publication bias and strategic non-disclosure do not appear to drive the results. I conclude that individual scientists benefit marginally from higher quality research, but that pharmaceutical companies lack strong incentives to drive improvement in trial quality.
Chapter 3 (with David Cutler and Thomas Getzen) studies the contribution of medical care to life expectancy gains. Using two hundred years of national and Massachusetts data on medical care and health, we examine how central medical care is to life expectancy gains. While common theories about medical care cost growth stress growing demand, our analysis highlights the importance of supply side factors, including the major public investments in research, workforce training and hospital construction that fueled a surge in spending over the 1955-1975 span. There is a stronger case that personal medicine affected health in the second half of the twentieth century than in the preceding 150 years. Finally, we consider whether medical care productivity decreases over time, and find that spending increased faster than life expectancy, although the ratio stabilized in the past two decades.