Trait anger is defined as a relatively stable personality trait that is manifested in the frequency, intensity, and duration of feelings associated with anger. People with high trait anger have rage and fury more often, more intensely, and with long-laster episodes than people with low trait anger. It is thought that people with high trait anger might be particularly susceptible to coronary heart disease; 12,986 participants were recruited for a study examining this hypothesis. Participants were followed for five years. The following table shows data for the participants identified as having normal blood pressure

(normotensives).

(a) What percentage of participants have moderate anger scores?

(b) What percentage of individuals who experienced a CHD event have moderate anger scores?

(c) What percentage of participants with high trait anger scores experienced a CHD event (i.e., heart attack)?

(d) What percentage of participants with low trait anger scores experienced a CHD event?

(e) Are individuals with high trait anger more likely to experience a CHD event than individuals with low trait anger? Calculate the relative risk of a CHD event for individuals with high trait anger compared to low trait anger.

(f) Researchers also collected data on various participant traits, such as level of blood cholesterol (measured in mg/dL). What graphical summary might be useful for examining how blood cholesterol level differs between anger groups?

Trait Anger Score Low Moderate High Total Yes 53 110 27 190 CHD Event No 3057 4704 606 8284 Total 3110 4731 633 8474