Browsing by Subject "cost-effectiveness analysis"

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    Essays on Innovation in the Medical Device Industry
    (2021-07) Everhart, Alexander
    This dissertation includes three empirical papers on the development and adoption of medical devices in the United States. Economists attribute as much as half of recent gains in life expectancy in the United States to the use of new medical technologies. When developing medical technologies, manufacturers must consider the “total product lifecycle” of devices, spanning from development costs to regulatory approval to insurer coverage and ultimately patient and physician adoption. The three chapters of this dissertation examine different stages of the total product lifecycle for medical devices.In Chapter 1, I study how medical device firms change their investments in research and develop following external shocks to production costs. Using damage to device manufacturing facilities caused by Puerto Rican hurricanes as a natural experiment, I find that increases in storm exposure cause firms to spend less on research and development and bring fewer medical devices to market. I also find that devices brought to market following storms are cited in competitor regulatory submissions no more or less often than the average medical device. This suggests that device firms do not meaningfully target more or less scientifically innovative projects at the margin when reducing investments in research and development. In Chapter 2, I describe the availability of cost-effectiveness analyses for medical devices in the United States. Cost-effectiveness analyses are not consistently used by insurers when making coverage decisions in the United States. I find that one of the barriers to using cost-effectiveness analyses is the timing of when analyses become available. Cost-effectiveness analyses are not available until several years after regulatory approval. In Chapter 3, I examine the effect of industry payments on physicians’ adoption of Medtronic’s Micra leadless pacemaker in fee-for-service Medicare. Leadless pacemakers have lower complication rates but a higher cost compared to traditional leaded pacemakers. I find that physicians who receive more payments from pacemaker manufacturers are more likely to adopt leadless pacemakers. However, this relationship is not robust to either physician fixed effects or an instrumental variables analysis predicting receipt of manufacturer payments as a function of distance from Medtronic headquarters.
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    Identifying Optimal Cervical Cancer Prevention Strategies for HIV-positive Women in Senegal, West Africa – Quantification of the Natural History of HPV Among HIV-positive Women and Markov Cohort Cost-Effectiveness Analyses
    (2015-05) Whitham, Hilary
    Objective. The interaction between human immunodeficiency virus (HIV) and human papillomavirus (HPV) results in an increased burden of cervical cancer among HIV-positive women. This research aims to shed light on the important topic of HIV/HPV co-infection with the goal of informing HPV disease prevention efforts. Specifically, using longitudinal data we estimated the natural history of HPV and cervical cancer among HIV-positive women to inform cost-effectiveness modeling aimed at identifying optimal targeted prevention approaches for this high-risk population. Methods. In total 1,277 women (45% positive for HIV-1 and/or HIV-2) were followed for an average of two years in Senegal, West Africa between 1994 and 2010. Cytology and HPV DNA testing were performed at approximately 4-month intervals. Competing risk modeling was used to estimate rates for transitioning between three clinical relevant natural history stages (Normal, HPV, and HSIL) for HIV-positive and HIV-negative women separately. Markov cohort modeling was used to simulate the impact of various cervical cancer screening strategies among HIV-positive women. Specifically, we compared the relative cost-effectiveness of six screening strategies (Hybrid Capture 2 HPV testing, rapid HPV testing, cytology, visual inspection with acetic acid (VIA), HPV testing followed by cytology triage, and HPV testing followed by VIA triage) and five screening frequencies using projected life expectancy and incremental cost-effectiveness ratios (ICER). Further, the potential cost-effectiveness of HPV vaccination at the time of HIV diagnosis was simulated under various theoretical effectiveness scenarios. One-way and probabilistic sensitivity analyses were conducted to explore the impact of uncertainty on results. Results. HIV-positive women had significantly higher rates of progression and lower rates of regression compared to HIV-negative women (i.e. adverse transitions). Among those with HIV infection with multiple HPV types, HPV-16/18, HIV-1, and CD4+ count <200 were associated with adverse transitions. Across a broad range of screening scenarios, VIA was identified as the most cost-effective and contextually feasible screening approach. Compared to no screening, annual VIA resulted in an average discounted increased life expectancy of 1.7 months and a 40% reduction in cervical cancer incidence with an ICER of I$1,500 per life year saved. High underlying HPV prevalence among HIV-positive women significantly reduced the cost-effectiveness of HPV testing. HPV vaccination was only cost-effective under optimal vaccine efficacy and/or costing scenarios. Specifically, with costs ≥I$31 vaccination became dominated when vaccine efficacy fell below approximately 70% and 40% for reducing transitions from Normal to HPV-16/18 and HPV-Other states, respectively. Conclusions. High rates of adverse transitions indicate that targeted screening for the growing population of HIV-positive women in Africa is needed. Based on World Health Organization criterion for cost-effectiveness, targeted VIA screening represents an important prevention opportunity among this high-risk population. With lower vaccine-induced titer levels reported among adult HIV-positive women and a potential corresponding reduction in vaccine efficacy, HPV vaccination costs must be reduced for primary prevention to be cost-effective in comparison to screening. Efforts to implement targeted screening, reduce vaccine costs, develop therapeutic vaccines, and evaluate upcoming HPV antiviral treatments should be made.