College of Agriculture
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As the foundation of the land grant mission at Montana State University, the College of Agriculture and the Montana Agricultural Experiment Station provide instruction in traditional and innovative degree programs and conduct research on old and new challenges for Montana’s agricultural community. This integration creates opportunities for students and faculty to excel through hands-on learning, to serve through campus and community engagement, to explore unique solutions to distinct and interesting questions and to connect Montanans with the global community through research discoveries and outreach.
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Item Determinants of delayed detection of cancers in Texas Counties in the United States of America(2012-05) Gong, Gordon; Belasco, Eric J.; Hargrave, K. A.; Lyford, C. P.; Phillips, B. U. Jr.Introduction: Previous studies have shown that delayed detection of several cancers is related to socioeconomic deprivation as measured by the Wellbeing Index (WI) in Texas, the United States of America (USA). The current study investigates whether delayed cancer detection is related to lack of health insurance, physician shortage and higher percentages of Hispanics rather than WI per se since these factors are directly related to delayed cancer detection and may confound WI. Methods: Cancer data and potential determinants of delayed cancer detection are derived from Texas Cancer Registry, Texas State Data Center, and Texas Department of State Health Services and U.S. Census Bureau. Texas cancer data from 1997 to 2003 are aggregated to calculate age-adjusted late- and early-stage cancer detection rates. The WI for each county is computed using data from the USA Census 2000. A weighted Tobit regression model is used to account for population size and censoring. The percentage of late-stage cancer cases is the dependent variable while independent variables include WI and the aforementioned potential confounders. Results: Delayed detection of breast, lung, colorectal and female genital cancers is associated with higher percentage of uninsured residents (p < 0.05). Delayed detection is also associated with physician shortage and lower percentages of Hispanics for certain cancers ceteris paribus ( p < 0.05). The percentage of late-stage cases is positively correlated with WI for lung, and prostate cancers after adjusting for confounders ( p < 0.05). Conclusions: The percentages of uninsured and Hispanic residents as well as physician supply are determinants of delayed detection for several cancers independently of WI, and vice versa. Identification of these determinants provides the evidence-base critical for decision makers to address specific issues for promoting early detection in effective cancer control.Item Correlation of the Ratio of Metastatc to Non-Metastatic Cancer Cases With the Degree of Socioeconomic Deprivation Among Texas Counties(2011-02) Phillips, Billy U. Jr.; Gong, Gordon; Hargrave, Kristopher A.; Belasco, Eric J.; Lyford, Conrad P.Background: Previous studies have demonstrated that cancer registrations and hospital discharge rate are closely correlated with census data-based socioeconomic deprivation indices. We hypothesized that communities with higher degrees of socioeconomic deprivation tend to have a higher ratio of metastatic to non-metastatic cancer cases (lung, breast, prostate, female genital system, colorectal cancers or all types of cancers combined). In this study, we investigate the potential link between this ratio and the Wellbeing Index (WI) among Texas counties. Results: Cancer data in 2000 were provided by the Texas Cancer Registry, while data on the ten socioeconomic variables among the 254 Texas counties in 2000 for building the WI were obtained from U.S. Census Bureau. The ten socioeconomic status variables were subjected to the principal component analysis, and the first principal component scores were grouped into deciles for the WI (1 to 10) and the 254 Texas counties were classified into 10 corresponding groups. Weighted linear regression analyses and a Cochran-Armitage trend test were performed to determine the relationship between the ratio of age-adjusted metastatic to non-metastatic cancer incidence cases and WI. The ratios of metastatic to non-metastatic cases of female genital system cancer (r2 = 0.84, p = 0.0002), all-type cancers (r2= 0.73, p = 0.0017) and lung cancer (r2= 0.54, p = 0.0156) at diagnosis were positively correlated with WI. Conclusions: The ratios of metastatic to non-metastatic cases of all-type, female genital system and lung cancers at diagnosis were statistically correlated with socioeconomic deprivation. Potential mediators for the correlation warrant further investigation in order to reduce health disparities associated with socioeconomic inequality.Item Socioeconomic deprivation as a determinant of cancer mortality and the Hispanic paradox in Texas, US(2013-04) Gong, Gordon; Belasco, Eric J.; Markide, K.; Phillips, B. U. Jr.Introduction: We have recently reported that delayed cancer detection is associated with the Wellbeing Index (WI) for socioeconomic deprivation, lack of health insurance, physician shortage, and Hispanic ethnicity. The current study investigates whether these factors are determinants of cancer mortality in Texas, the United States of America (USA). Methods: Data for breast, colorectal, female genital system, lung, prostate, and all-type cancers are obtained from the Texas Cancer Registry. A weighted regression model for non-Hispanic whites, Hispanics, and African Americans is used with age-adjusted mortality (2004–2008 data combined) for each county as the dependent variable while independent variables include WI, percentage of the uninsured, and physician supply. Results: Higher mortality for breast, female genital system, lung, and all-type cancers is associated with higher WI among non-Hispanic whites and/or African Americans but with lower WI in Hispanics after adjusting for physician supply and percentage of the uninsured. Mortality for all the cancers studied is in the following order from high to low: African Americans, non-Hispanic whites, and Hispanics. Lung cancer mortality is particularly low in Hispanics, which is only 35% of African Americans’ mortality and 40% of non-Hispanic whites’ mortality. Conclusions: Higher degree of socioeconomic deprivation is associated with higher mortality of several cancers among non-Hispanic whites and African Americans, but with lower mortality among Hispanics in Texas. Also, mortality rates of all these cancers studied are the lowest in Hispanics. Further investigations are needed to better understand the mechanisms of the Hispanic Paradox.Item The impact of rural health care accessibility on cancer-related behaviors and outcomes(Springer, 2014) Belasco, Eric J.; Gong, Gordon; Pence, Barbara; Wilkes, Ethan C.Background: This research seeks to identify the relationship between economic factors related to the ability to receive and pay for health services and adverse cancer outcomes, as well as preventative screening and behavioral factors that influence the risk of cancer. We focus on the Northern High Plains region, where we are able to compare regions with extremely low access to health services with those with relatively high levels of access. Objective: This study aims to identify health disparities in rural communities, particularly among Native American populations, and, thereby, begin to determine the most effective means by which to deliver health services to areas where geography, economics, and culture might prevent traditional models of health delivery from providing sufficient incentives for the prevention of adverse cancer-related outcomes. Methods: The Health Care Accessibility Index (HCAI) is computed through the use of principal component analysis and includes economic variables as well as variables concerning institutional and geographic access to health care. Index values are then regressed onto cancer outcomes, cancer-prevention outcomes, and cancer-related risk, using weighted least squares and quantile regressions. Results: Counties with relatively poor access to health care (low HCAI) also have statistically (1) lower breast cancer screening rates, (2) higher smoking prevalence, and (4) higher cancer-related mortality rates. Breast cancer screening is found to be especially sensitive to areas of low health accessibility. Conclusions: Empirical results provide support for policy efforts to increase the accessibility of health care services that are targeted to areas with mammography screening rates, high obesity rates, high smoking prevalence, as well as areas near Native American reservation territories.