Question

People who get angry easily tend to have more heart disease. That is the conclusion of a study that followed a random sample of 12,986 people from three locations for about four years. All subjects were free of heart disease at the beginning of the study. The subjects took the Spielberger Trait Anger Scale test, which measures how prone a person is to sudden anger Displayed are data for the 8474 people in the sample who had normal blood pressure. CHD stands for "coronary heart disease," which includes people who had heart attacks and those who needed medical treatment for heart disease.

low anger moderate high anger Total
CHD 53 110 27 190
No CHD 3057 4621 606 8284
Total 3110 4731 633 8474
Does the data support the study's conclusion about the relationship between anger and heart disease?
STATE: Is the level of anger associated with coronary heart disease (CHD)?
PLAN: The chi-square tests the null hypothesis, "There is no relationship between anger level and coronary heart disease (CHD)."
SOLVE: Are the conditions for using the chi-square test met?
a)Yes
b)No

Answer 1

The presented data indicates that the prerequisites for performing a chi-square test are satisfied, and the test would be valid to examine the relationship between anger levels and coronary heart disease. Existing research corroborates the premise that anger and hostility are risk factors for cardiovascular diseases.

Step-by-step explanation:

The question pertains to whether the level of anger is associated with coronary heart disease (CHD) and if the data supports the study's conclusion. To determine this, a chi-square test is suitable for examining the relationship between two categorical variables: anger level and the presence of CHD. For the chi-square test to be appropriate, certain conditions must be met, such as a large enough sample size, independent observations, and expected frequencies of at least 5 in each cell of the contingency table. Given the data provided, with a total sample of 8474 participants, these conditions seem to be met, indicating a chi-square test is valid for this analysis.

According to the Spielberger Trait Anger Scale, the study categorized people into three groups based on their propensity to anger: low, moderate, and high. The occurrence of coronary heart disease among these groups was tracked. Considering that the study found varying numbers of CHD cases among the different anger levels, it suggests there might be a relationship between anger level and the likelihood of developing CHD.

Extensive research in the field of medicine and health psychology, such as the work by Chida and Steptoe (2009), supports the association between anger, hostility, and adverse cardiovascular outcomes. This includes findings that negative emotional states and Type A behavior, which often encompasses anger, are significant risk factors for the development of heart diseases. The consistent patterns across studies indicate that there is a correlation between anger and heart disease.