Chapter 2 Literature Review

(King et al., 2020)

In this study, the authors performed a national survey of a sample of US outpatient practices delivering primary care to determine the prevalence of detailing and sample closets, two common pharmaceutical industry practices for marketing.

The authors distributed surveys to nearly 5000 practices across the country, with representation from practices of different sizes, levels of privatization, and academic affiliation. This study concluded that these marketing practices were substantial in outpatient practices delivering primary care in the United States, particularly in smaller practices, those outside of systems, or those without academic affiliation.

King et al. provides important context for this study, highlighting the frequency of these interactions between primary care providers and the pharmaceutical industry. As the authors note, their findings may “reflect limited infrastructure in these practices to impose access restrictions or provide independent drug information,” to the potential detriment of patient and community-level health.

(Mitchell et al., 2021)

This study more closely examines the tangible impacts of transactional relationships between physicians and the pharmaceutical industry. Specifically, the authors explore whether there is a concrete impact on physician prescribing practices when receiving financial or material incentives from pharmaceutical companies.

To do this, the authors observed 36 studies comprising 101 analyses into the impacts of financial incentives on physician practices. This review concluded that there is a positive association between payments and physician practices, with a majority of the studies finding only positive associations and the remainder with both positive and null findings.

Considering this study in conjunction with King et al., it follows that pharmaceutical companies are frequently targeting outpatient facilities providing primary care, and their incentives influence physicians’ prescribing practices. Thus, it is important to understand where these payments are going and how they have changed over time to examine where primary care physicians may be the most susceptible to excessive pharmaceutical industry pressure.

(Marshall et al., 2020)

This study sought to determine trends in physician-level payments to evaluate whether the implementation of Open Payments has been associated with a decrease in the prevalence or value of physicians’ interactions with industry. It did so via a retrospective, population-based cohort of physicians practicing in the United States from 2014 to 2018. Payment values for non-research purposes were aggregated for each physician for each calendar year.

The study concluded the proportion of physicians receiving payments from industry decreased from 2014 to 2018. This trend held across all physician specialties. However, the study further found that total and annual payment amounts remained relatively stable across the time period of interest.

While this study explores the industry-physician interaction, it focuses primarily on differences between physicians of varying specialties, rather than focusing on one specialty in particular. Likewise, it focuses on payments to individual physicians but does not factor in spatial considerations.

(Inoue et al., 2019)

This study, similarly, sought to investigate the association between physician characteristics and the value of industry payments. Using data in the Open Payments system from 2015-2017, the authors more closely examined how characteristics, such as sex, years of practice, and medical school attended, impacted a physician’s relationship with and payment by the pharmaceutical industry. By accounting for other factors, this study was able to compare physicians practicing at the same institution.

Whereas Marshall et al. examined only general payments (any non-research related transfers of value), this study analyzed general, research, and ownership - payments made in the form of royalties or for licenses - payments.

This study concluded that the top 5% of physicians received 91% of industry payments. If comparing physicians within the same institution, physicians who were male, physicians who had been practicing for 21-30 years, and who attended a medical school ranked in the top 50 nationally received higher payments from industry. These insights are important when comparing physicians on an individual basis, while the first conclusion provides important context for considering payments nationally. However, again, these conclusions are limited spatially, as they don’t account for differences in different areas of the country.

(Cuomo et al., 2021)

The study by Cuomo et al. is the most comparable to this very study, as its objective is to analyze physician-industry relationships by specialty type, payment type, geospatial trend, and longitudinal trend between 2014–2018. Likewise using general payments from the Open Payments system, this study aggregated based on the aforementioned characteristics to draw observational conclusions.

In the first section of the analysis, the authors examine the distribution of payments to 36 specialties. Notably, Family Medicine and General Practice – two of the categories which this study aggregates into Primary Care – fall within the bottom 6 of these 36 specialties.

Thus, when considering the other areas of analysis – payment type, geospatial, and longitudinal – one must consider the limited representation of payments to physicians of these two specialities of interest. However, primary care, and as a result primary care physicians, is the first place many Americans seek treatment and develop a relationship with the healthcare industry. Therefore, this study aims to draw particular focus to these specialties with respect to these areas of analysis.