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Many studies have demonstrated that high blood pressure increases the risk of developing heart disease or having a stroke. It is also safe to say that the health risks associated with binge drinking far outweigh any benefits. A study published in Heath Magazine in 2010 suggested that a combination of the two could be a lethal mix. As part of the study that followed 6100 South Korean men aged 55 and over for two decades, men with high blood pressure who binge drank even occasionally had double the risk of dying from a stroke or heart attack when compared to teetotalers with normal blood pressure. a. Is this an observational or experimental study? b. Identify the explanatory and response variable(s). c. Does the study prove that a combination of high blood pressure and binge drinking causes an increased risk of death by heart attack or stroke? Why or why not?

Short Answer

Expert verified
a. Observational study. b. Explanatory: High blood pressure, binge drinking; Response: Risk of death by heart attack or stroke. c. No, correlation is shown but not causation.

Step by step solution

01

Determine the Type of Study

This study observed a group of individuals and recorded data about their lifestyles and health outcomes over time without manipulating any variables. Therefore, it is an observational study, as the researchers did not intervene or assign subjects to treatment or control groups.
02

Identify the Variables

The explanatory variables in the study are high blood pressure and binge drinking, as these factors were observed to assess their effect. The response variable is the risk of dying from a stroke or heart attack, as this is the outcome the study is measuring in response to the explanatory variables.
03

Analyze Causation

The study does not prove causation because it is observational. While it shows a correlation between high blood pressure, binge drinking, and increased risk of death, it does not establish a direct cause-and-effect relationship due to potential confounding variables and the lack of experimental control.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Explanatory Variable
In the context of this study concerning high blood pressure and binge drinking, the explanatory variables are the factors that the researchers believe could influence the outcome. Here, the explanatory variables are high blood pressure and binge drinking. These are the variables that are expected to have an impact on the risk of death from a stroke or heart attack.
These are referred to as explanatory because they help in explaining the variations observed in the response variable. By analyzing these variables, researchers aim to understand the conditions that might affect the likelihood of the studied outcomes occurring. Explanatory variables are pivotal in guiding the direction of a study and help in forming the basis of the hypotheses being tested.
It's important to note that in observational studies like this one, the explanatory variables are merely observed rather than controlled or manipulated by the researchers. So, while they are central to the study's inquiry, they do not possess an inherent proof-giving capacity about causation.
Response Variable
The response variable in any study displays the outcome or the effect that the explanatory variables are presumed to influence. In this study, the response variable is the risk of dying from stroked or heart attacks. Essentially, it is the variable of interest that researchers are keen to observe and measure.
To simplify, this is the 'result' part of the experiment or study. Researchers seek to understand how the explanatory variables (high blood pressure and binge drinking) could potentially affect this particular outcome. In the realm of data analysis, the response variable's changes or occurrences directly depend on the explanatory variables, helping researchers to identify any significant patterns or relationships.
This distinction is vital, especially in observational studies, because understanding the intricacies of how the response variable behaves, assists in drawing insightful conclusions—though, with limitations, given the lack of randomization and manipulation.
Correlation vs Causation
A frequent point of confusion in studies is distinguishing between correlation and causation. Correlation means that two variables appear to have a relationship, whereas causation indicates that one variable actually produces an effect on the other. In the context of this study, the observation that high blood pressure and binge drinking appear to increase the risk of death from a stroke or heart attack is a correlation.
The critical aspect here is understanding that the study, by being observational, highlights a relationship but does not prove that one action directly caused the outcome. This is because there could be other lurking variables, known as confounding variables, that could also affect the outcome. For example, lifestyle factors or genetic predispositions might play a role but aren't accounted for directly in the study.
Experimental studies, unlike observational ones, allow for more control over variables, which helps in establishing a causative relationship. But in this case, since no such control was executed, it remains a correlation, emphasizing the association without asserting definitive causation.

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