× Limited Time Offer ! FLAT 20-40% off - Grab Deal Before It’s Gone. Order Now
Connect With Us
Order Now

PUBH6005 Epidemiology Report Sample

Context

In Part B, you are able to apply their knowledge of causation and association. The skills gained from this assessment allows you to make a judgement on causality and association based on the epidemiological research and evidence. You will demonstrate your ability to apply the Bradford Hills criteria, a key tool in determining association and causality within epidemiological studies. Establishing association and causality are key skills in epidemiological disease investigation.

Task

Part B requires you to choose one of the articles that you have critically appraised in Part A, and using the Bradford Hills criteria as a guide, write within 1000-words on your judgment of association and causation. You will need to provide your opinion/decision/recommendations for a couple of the Bradford Hills criteria. Headings can be utilised where required. You may need to search for additional research articles to support your findings. Please refer to the Instructions for details on how to complete this task.

Instructions

Select 1 of the 2 articles that you critically appraised in Part A. Address a couple of Bradford Hill’s Criteria's to present your opinion/decision/recommendation in establishing the causality and association of the findings. Your assessment should include should include the following:

1 Give the title of the article and introduce the objective of the paper
2 CHOOSE ANY TWO of the following criteria's and and address them accordingly
2.1 Temporality
2.2 Strength of association
2.3 Consistency
2.4 Dose-response relationships
2.5 Biological plausibility
2.6 Specificity
2.7 Experimental data
2.8 Coherence
2.9 Analogy

Solution

Introduction:

The paper aims to apply Bradford Hill’s criteria to a chosen article to determine the causality of the article. In the year, 1965, 9 viewpoints have been published by Austin Bradford Hill in order to check whether the “epidemiologic associations” are causal. These criteria have been the popularly used for determining “causal inference” within epidemiologic studies. Here in this article, two of Bradford Hill’s Criteria have been chosen to establish the causality (Shimonovich et al., 2020). For Assignment Help These two factors are “temporality” and “strength of association”. “Strength of Association” is basically critical to the ‘assessment of significant causal relationships” (Fedak et al., 2015). Temporality on the other hand is perhaps the only aspect which is agreed to is important to the “causal inference” (Fedak et al., 2015).

Title of the Chosen Article: “Case-Control Study of Risk Factors for Human Infection with a New Zoonotic Paramyxovirus, Nipah Virus, during a 1998–1999 Outbreak of Severe Encephalitis in Malaysia” by Parashar et al., (2000).

Purpose/Object of the paper:

The article mainly discusses the outbreak of “encephalitis” that had affected 265 patients and amongst them, 105 got fatally affected by the virus between 1998 and 1999 within Malaysia. This outbreak was associated with the “paramyxovirus, Nipah”. This is the virus that affected human beings, pigs, cats and dogs (Parashar et al., 2000). The main purpose of the chosen article is thus to examine and to determine the aspects of exposures to Nipah infection amongst human beings while the outbreak of the encephalitis tool place (Parashar et al., 2000).

Assessment of two Bradford Hill’s criteria:

Temporality:

Temporality is regarded as one of the most important criteria for a “causal association” amongst a particular “exposure” and an effect. In other words, the exposure should precede the effect, though it is not required to measure the exposure before measuring the effect (Fedak et al., 2015). Also, it has been explained by Bradford that in the criteria where the relationship between the cause and the effect is casual in case cause or the exposure results in the onset of the infection or the disease (Cox, 2018).

Within the temporality criteria, the effect or the outcome has to take place after the cause and if there is any delay after the cause or the exposure occur, the effect takes place after that delay. The chosen article by Parashar et al., (2000) conducts a case-control study in order to characterize the exposures linked with the “Nipah Infection” of the human beings during the spread of the virus. This study suspected an association of “human Nipah infection” and the “proximity to sick pigs” earlier than the outbreak as most patients were “male pig farmers”. Also, the “viral isolates” from the infected pigs and from the “encephalitis patients” demonstrated the same sequence of nucleotides. Applying Bradford Hill’s Temporality criterion here, it can be said that the cause here is the exposure to the sock pigs or proximity to the infected and the outcome of the effect is the “human Nipah infection” (Cox, 2018). It is clearly observed from the study that after the exposure to the sick pigs takes place, the pig farmers get infected by the virus and thus temporality can be justified here to be causal. Another demonstration of the study that justified the temporality criterion of the article to be causal is that the outbreak was stopped after the “pigs” were slaughtered and were buried. Thus, it can be said that the direct contact of the proximity of the human first took and then the effect, that is the infection within the human body took place and thus cause had clearly preceded the effect.

Strength of Association:

The “Strength of Association” is one of the most important criteria amongst the 9 criteria proposed by Bradford Hill for measuring the causality of an epidemiology study. He explained that the greater the relationship between the “diseases” and the “exposure”, the more it is likely to be causal (Shimonovich et al., 2020). In other words, the stronger the risk magnitude of the association between the “risk factor” and the resultant disease the more probable it is for the relationship to be “causal”. In order to study the relationship between the Nipah infection in humans and the exposure to infected pigs, case patients and control subjects have been chosen (Fedak et al., 2015).

After carrying out the case-control analysis of the study, the activities involving proximate contacts with pigs have been combined in the form of a “single variable”. The study of the results of the article suggests that the exposure to the infected pigs (cause) is potentially associated with the “effect” that is the Human Nipah infection with 86% of “case-patients” as compared to 50% of control subjects (Fedak et al., 2015). In addition, Bradford Hill’s “Strength of Association” criterion can thus be verified here and thus the relationship is said to be causal the as the findings of the study suggests that there is a potential strength of association between the cause (contact to sick pigs) and the effect (Nipah infected humans) and also show that the activities like close proximity with the infected pigs were associated with the “infection”. This argument can be further strengthened by considering the fact the outbreak was prevented by slaughtering and burying the pigs (Fedak et al., 2015). The strength of association is very significant here and thus the relationship is “causal” (Shimonovich et al., 2020).

Conclusion:

In this study, two of Bradford Hill’s criteria have been applied on the study by Parashar et al., (2000) and the application and the analysis of these two criteria on the study demonstrates and establishes a strong causal relationship between the “presumed cause” (contact with sick pigs) and the “observed effect” (Nipah infection in humans). It can thus be concluded that there is a close association between proximity with encephalitis infected Pigs and Human Nipah infection and thus the exposure to these pigs can be considered as the primary source of the disease.

References:

Fill the form to continue reading

Download Samples PDF

Related Sample

Assignment Services