Which is true of the causal pie model?
A) Each ‘pie’ represents all component causes needed to be sufficient to produce a case
B) If due to an infectious agent, all slices must be the infectious agent
C) Can be described visually with a triad
D) Only useful for analyzing diseases with a single cause
The correct answer and explanation is:
The correct answer is A) Each ‘pie’ represents all component causes needed to be sufficient to produce a case.
Explanation:
The causal pie model is a framework used to understand the various component causes that lead to the occurrence of a particular event or disease. The model is often used in epidemiology to illustrate how different factors or conditions contribute to the development of a disease or health outcome.
In the causal pie model, each “pie” represents a sufficient cause for an event, and each slice of the pie represents a necessary component cause. A sufficient cause is a complete set of conditions that can produce the effect. To develop a disease, not all of the component causes may be necessary in every case; different combinations of causes may be required depending on the situation.
Why A is correct:
Each “pie” in the model includes all the necessary components that, when combined, will lead to the occurrence of a disease. This highlights that a disease may require multiple causes, but when combined, they form a complete “sufficient cause.”
Why other options are incorrect:
- B) If due to an infectious agent, all slices must be the infectious agent: This is not true. In the causal pie model, an infectious agent may be one component cause, but other factors (like environmental, genetic, or host factors) may be needed to complete the sufficient cause.
- C) Can be described visually with a triad: This is inaccurate. A “pie” is typically represented as a circle divided into slices, not as a triad. A triad is more commonly associated with the epidemiological triangle, which consists of the agent, host, and environment.
- D) Only useful for analyzing diseases with a single cause: This is not true. The causal pie model is designed specifically to analyze diseases with multiple component causes. It is not restricted to diseases with only a single cause.
Thus, the causal pie model is useful for illustrating complex interactions among various factors that contribute to disease, making A the correct choice.