OBSERVATIONAL STUDY FACT SHEET

WHAT WAS THE PURPOSE OF THE OBSERVATIONAL STUDY?

The WHI observational study (OS) had several goals. These goals included:

• To give reliable estimates of the extent to which known risk factors to predict heart disease, cancers and fractures;
• To identify "new" risk factors for these and other diseases in women;
• To compare risk factors, presence of disease at the start of the study, and new occurrences of disease during the WHI across all study components; and
• To create a future resource to identify biological indicators of disease, especially substances and factors found in blood.

HOW WAS THE OBSERVATIONAL STUDY CONDUCTED?

The observational study enlisted 93,676 postmenopausal women between the ages of 50 to 79. The health of OS participants was tracked over an average of eight years.

Women who joined this study filled out periodic health forms and also visited the clinic three years after enrollment. OS participants were not required to take any medication or change their health habits. It did, however, follow a woman's health over a long period of time.

The OS provided information that complemented that obtained in the CT.