Agricultural Health Research Study: Critical Review of Article - Assignment Example

Epidemiology Study: Critical Review of Article What type of epidemiological study is this? Though Carr et al (2007) s that there is no single agreed classification of epidemiological studies, the study in the article are a cohort epidemiological research. Aschengrau and Seage (2008) denote that a cohort study is a study conducted on healthy people with different degrees of exposure to a disease causing agent and evaluates what happens to the people over time. The Agricultural Health study in the article employs the use of healthy private and commercial pesticide participants in order to determine exposure to Atrazine pesticide and the prevalence of cancer among the participants. Exposure comes first before the health outcome, which is a condition essential for causation. Needless to say, the study is not exposed to bias as the examination of exposure is before the health status identification (Susan et al, 2007). The Agricultural Health Research Study aims to identify the commonality of cancer disease, a characteristic that typifies a cohort study (Freeman et al, 2011). 2. What scientific question(s) was posed in this study? Scientific questions are used to investigate a phenomenon. In reference to Hennekens and Buring (1987), scientific questions can either be qualitative or quantitative. In the research study in the article, the scientific questions used in the study are quantitative, scientific research questions. Scientific quantitative questions are questions which are employed in a qualitative research (Andrews, 2003). Debatably, a quantitative research is a scientific study that aims at gathering data and figures (Hennekens & Buring, 1987). Examples of the questions employed questioned the participant’s use of the 50 most common pesticides, mixing and application methods and the use of protective equipments. In addition, the questions also enquired on the participant’s potential cancer risk factors such as smoking, drinking, demographic information, and cancer history in relatives. Some of the questions used aimed at identifying the number of days a participant had been exposed to pesticides, especially Atrazine. Such questions aimed at identifying the degree of exposure. 3. What background information did they provide to support the questions asked in this study? The objective of the Agricultural Health Study was to identify the relationship between exposure to Atrazine and prevalence of cancer among the applicators. In order to identify the association, the study employed questions to identify whether the applicant had been exposed to any other cancer potential factor such as smoking or alcohol consumption and cancer history. The research also uses the questions to identify the number of days that the participant has been exposed to Atrazine (Freeman et al, 2011). In addition, the authors constructed the questions in order to determine the two assessments of Atrazine use among the participants. The first assessment was the number of days of exposure to Atrazine by multiplying the number of years the participant had been exposed to Atrazine by the standard days exposed to Atrazine in a year (Freeman et al, 2011). The second assessment was concentration credence days of use by evaluation of exposure to Atrazine through mixing and application. These assessments obtained information from the questionnaires administered to the participants. Arguably, the Agricultural Health Research Study administered the questionnaires to the participants in order to obtain relevant information that could be used to show the relationship between Atrazine use and cancer. 4. What study population did they use? How did they identify study participants? What were the exclusion and inclusion criteria? The Agricultural Health study used certified insect killer appliers in Lowa and North Carolina. The research incorporated private applicators from North Carolina who are primarily farmers. On the other hand, the research incorporated both private and money-making appliers. While selecting the applicators to use in the study, occurrence cases of cancer were determined via connection to National Cancer registers in North Carolina and Lowa. Foremost the Agricultural Health study included the cancer cases treated from conscription through 31st December 2007 to the analysis (Freeman et al, 2011). The participants selected for the study were annually compared to the State Mortality catalog to recognize pivotal position, present contact information of the Domestic income service, pesticide registries of nation agricultural departments and automobile muster offices to determine their residence in North Carolina and Lowa. In order for the research to proceed, the participants had to show consent to the study (Freeman et al, 2011). 5. What was the health outcome of interest and how is it assessed? The research identified that the pesticide applicators are whites and male. The research also identified that the private appliers were more probable to have been exposed to atrazine than the commercial appliers. Nonetheless, the number of commercial applicators reported many days per year and aggregate life span usage of atrazine than the clandestine appliers (Freeman et al, 2011). In 2007, there were 4737 cancer incidences identified among 53662 applicators, in addition to 1785 cancer cases, which had been identified earlier. In reference to the results obtained from the research, there was no link between cancer and the use of atrazine. However, anchored in the 29 appliers exposed to atrazine, there were noteworthy associations between concentration-credence life days of atrazine use in the uppermost portion and thyroid cancer. Since thyroid cancer is also associated with obesity, the Agricultural Health study researchers altered the results for body mass index (Freeman et al, 2011). According to Freeman et al (2011), esophageal cancer was reported in the subsequent group of disclosure for concentration-credence life span days. This was measured by comparing it with the other categories which showed no cases of esophagus or oral cancer. In addition, the report identified that there is no link between breast cancer and atrazine. This was done by exposing 9 exposed and 27 unexposed female applicators. Moreover, use of atrazine did not show link with any lymphohematopoietic growth. This was done through possible outcome adaptation by employment of compounds asserted to interrelate with NHL and atrazine by carrying out an evaluation characterized by use of these chemicals. 6. What was the measure of association used in the study and what were the findings? The link between the use of atrazine and the likelihood of cancer was examined through the study by analyzing the data obtained in the study (Freeman et al, 2011). The relative risks of cancer incidence among the applicants were calculated through poison regression using SAS. The models for identifying the relationship between the use of atrazine and cancer were grouped into sex, race, age, smoking history, alcohol use, and education background. Identification of this association was through atrazine concentration-credence lifespan days of utilization in the different quartiles. The quartile of use that showed the highest atrazine intensity-weighted lifetime days had a high association with cancer (Freeman et al, 2011). The quartile that showed the lowest atrazine intensity-weighted lifetime days had a weak association with cancer. 7. Were there any biases or any other limitations of the study? Bias is a practical term for performing desires in classifying area under discussion or in measuring their experience or illness condition. According to Wang (2002), once a study has been prepared, and study subjects acknowledged, it is significant that the respondents are enlisted consistently and statistics on their wellbeing and experience gathered time after time. If definite themes are not registered in the study, or if data is obtained in a different way from, unlike subjects, the resultant prejudice could nullify the study. In the Agricultural Health cohort epidemiological study, the number of cancer cases as a result of atrazine has been identified. The research involved applicants who were exposed to atrazine and an analysis done after the associations between thyroid and esophagus cancer. This eliminated the chances of the researcher’s preference or biases which would have affected the research study. As a way of reducing the chances of biasness in any research study, researchers often make use of everyone selected for the study (Wang, 2002). This is because those who do not participate may be different from those who participate leading to biased research results. In the Agricultural Health study, there was full participation of all the applicators selected to take part in the research. In addition, the research used a credible criterion in identifying the applicators. In this regard, the applicants selected for the study were eligible. 8. What were the principal conclusions of this study? Analysis of the information obtained from the study indicates that there is no overall relationship between cancer and the intensity-weighted metric and the lifetime days exposed to atrazine. For most of the areas where cancer infests such as the lungs, thyroid and the esophagus, there was little or no relationship between atrazine use and cancer infection (Freeman et al, 2011). However, there was some relationship between atrazine concentration-weighted life span days of utilization in the uppermost group and thyroid cancer. Needless to say, despite the differences in patterns of pesticide utilization between the clandestine and business appliers there was no significant difference in the consequences for whichever cancer spot (Freeman et al, 2011). 9. Based on what you discussed above, do you agree or disagree with the conclusions? I do agree with the conclusions from the study. The research was well carried out and the applicators were well identified, and the results of the study were well analyzed. 10. What next steps would you propose to further research on this topic? This study does not identify the chemicals present in atrazine. The effects of pesticides and other industrial products can be well identified by studying the effects of their constituent chemicals. I would recommend that future research identifies the chemicals present in atrazine and evaluate each chemical according to the literature available (Silva & International Agency for Research on Cancer, 1999). In addition, I would recommend that the study incorporate applicators from different states in United States. The applicators used in the study were only from two regions. References Andrews, R. (2003). Research questions. London: Continuum. Aschengrau, A., & Seage, G. R. (2008). Essentials of epidemiology in public health. Sudbury, Mass: Jones and Bartlett Publishers. Carr, S., Unwin, N., & Pless-Mulloli, T. (2007). An introduction to public health and epidemiology. Maidenhead: Open University Press. Freeman, L. B., Rusiecki, J. A., Hoppin, J. A., Lubbin, J. H., Koutros, S., Andreotti, G., & Zahm, S. H. (2011). Atrazine and Cancer Incidence Among Pesticide Applicators inn the Agricultural Health Study. Environmental Health Perspectives, 119(9), 1253-1259. Hennekens, C. H., Buring, J. E., & Mayrent, S. L. (1987). Epidemiology in medicine. Boston: Little, Brown. Silva, I. S., & International Agency for Research on Cancer. (1999). Cancer epidemiology: Principles and methods. Lyon, France: International Agency for Research on Cancer. Wang, J. -D. (2002). Basic principles and practical applications in epidemiological research. Singapore: World Scientific. Read More