Contribution of H. pylori and Smoking Trends to US Incidence of Intestinal-Type Noncardia Gastric Adenocarcinoma: A Microsimulation Model

Background: Although gastric cancer has declined dramatically in the US, the disease remains the second leading cause of cancer mortality worldwide. A better understanding of reasons for the decline can provide important insights into effective preventive strategies. We sought to estimate the contribution of risk factor trends on past and future intestinal-type noncardia gastric adenocarcinoma (NCGA) incidence. Methods and Findings: We developed a population-based microsimulation model of intestinal-type NCGA and calibrated it to US epidemiologic data on precancerous lesions and cancer. The model explicitly incorporated the impact of Helicobacter pylori and smoking on disease natural history, for which birth cohort-specific trends were derived from the National Health and Nutrition Examination Survey (NHANES) and National Health Interview Survey (NHIS). Between 1978 and 2008, the model estimated that intestinal-type NCGA incidence declined 60% from 11.0 to 4.4 per 100,000 men, <3% discrepancy from national statistics. H. pylori and smoking trends combined accounted for 47% (range = 30%–58%) of the observed decline. With no tobacco control, incidence would have declined only 56%, suggesting that lower smoking initiation and higher cessation rates observed after the 1960s accelerated the relative decline in cancer incidence by 7% (range = 0%–21%). With continued risk factor trends, incidence is projected to decline an additional 47% between 2008 and 2040, the majority of which will be attributable to H. pylori and smoking (81%; range = 61%–100%). Limitations include assuming all other risk factors influenced gastric carcinogenesis as one factor and restricting the analysis to men. Conclusions: Trends in modifiable risk factors explain a significant proportion of the decline of intestinal-type NCGA incidence in the US, and are projected to continue. Although past tobacco control efforts have hastened the decline, full benefits will take decades to be realized, and further discouragement of smoking and reduction of H. pylori should be priorities for gastric cancer control efforts. Please see later in the article for the Editors' Summar

A Professional Ethics for Researchers?

Historical research has shown that, at its inception, research ethics was conceived as distinct from existing discourses of professional ethics. Subsequently, this distinction has been maintained and, as a result, the discourse of research ethics appears to be an external to and independent of the practices it normatively analyses and comments upon. This chapter challenges these founding preconceptions and considers if research ethics can be understood as a professional ethics. Therefore, this chapter examines the criteria sociological research identifies as constitutive of a profession, and while one might conclude that research is obviously not formally instantiated as a profession, some of the sociological criteria have significant relevance. In this light it is argued that we might rethink the notion of research ethics in terms of a professional ethics. To do so would be to more clearly embed ethical discourse in the practice(s) of research, something that is consistent with the current turn to integrity

Research ethics beyond the IRB: Selection bias and the direction of innovation in applied economics

Principles for ethical behavior in the context of research are codified into rules that may change over time to meet peoples’ needs in specific institutions, including universities and professional associations. This paper aims to spark discussion about a set of ethical choices beyond those addressed by an IRB or recent association policy statements. Our specific focus is topic selection and the role of researchers’ interests and incentives in determining the kinds of research that we do. Using the principle of induced innovation, we show how changing incentives can influence the direction of research effort and thereby affect the kinds of policies or technologies that are supported by available evidence. With this paper, we hope to generate discussion among applied economists about selection bias in research and how we can use insights from economics itself to guide topic selection.12 month embargo; published online: 07 January 2021This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]