Understanding Venn Diagrams

Incidence of Heart Attack Below 40 years of Age

We are interested in finding the probability of a heart attack below 40 years of age. Venn diagrams help visualize the scenario of people having heart attack before age of 40 including those with high blood pressure denoted by H, high sugar denoted by S and high cholesterol denoted by C or a combination of these. N denotes those individuals who have stroke before 40 and have blood pressure, sugar and cholesterol within normal limits. The image below shows the venn diagram of those cases where the blood pressure and sugar are beyond normal limits but cholesterol is within the limits.  This way all the possible causes resulting to a heart attack before 40 years can be minutely analyzed and it's probability can be calculated. This analysis is based on collected data and can aid in correct diagnosis.

This venn diagram shows probability of a stroke with high levels of blood pressure and blood sugar