Summary
The Health Insurance Plan of Greater New York (HIP) Breast Cancer Screening Trial was a randomized screening study designed to test if breast cancer mortality rates could be reduced through the use of periodic screening. Periodic screening was composed of an initial examination followed by 3 subsequent annual exams. Screening consisted of a clinical breast examination and mammography. The study concluded that periodic screening resulted in a reduced breast cancer mortality rate. The effect appeared to be concentrated in participants over the age of 50.
Study Years: 1963-1986
Randomized trial with two arms:
- Arms
- Arm I: Initial clinical breast examination and mammography followed by 3 annual screens.
- Arm II: Control arm.
Study Eligibility:
- Ages Eligible for Study: 40-64 Years
- Sexes Eligible for Study: Female
- Had to be enrolled in HIP for at least 1 year
- No prior breast cancer diagnosis
Enrollment
Enrollment: 60,695
- 30,565 in Control Arm
- 30,130 in Intervention Arm
- 20,146 Screened
- 9,984 Refused Sreening
Total Study Population Demographics (60,695 Randomized and Eligible People):
- Age (years):
- Mean: 50.88
- Range: 40-64
- Median: 51
The Schema is a timeline of the study. It indicates start/end points, visits expected, major testing to be done, and any other information that is crucial to understanding how the study was completed.
Schema Description
The study had participants split between the control and intervention arms. The intervention arm was scheduled for a clinical exam and mammography. If the participants attended the first exam they were scheduled for 3 subsequent annual exams. The control arm had no exams and women just received their usual medical care. There were mail surveys sent out 5, 10, and 15 years after trial entry. Death and cancer statistics were checked from a variety of sources including the National Death Index (after 1979), the New York Cancer Registry, HIP records, hospital claims files, and death records from several states.
Main Findings
Major analyses of the primary trial endpoints were conducted at the 5, 7, and 18 year intervals from randomization and found that screening reduced mortality that was largely seen in the participants over the age of 50.