Participant Cohorts
Participant Cohorts
There are six groups of participants in the Framingham Heart Study: Original Cohort, Offspring Cohort, Third Generation Cohort, New Offspring Spouse Cohort, Omni Generation 1 Cohort, and Omni Generation 2 Cohort.
To view a list of cohort examination dates and attendee summaries click here (last updated 11/3/2023).
For more information about each FHS cohort please select the cohort name below:
Original Cohort
AGE-SEX DISTRIBUTION AT ENTRY (1948) | ||||
---|---|---|---|---|
Age | 29-39 | 40-49 | 50-62 | Totals |
Men | 835 | 779 | 722 | 2,336 |
Women | 1,042 | 962 | 869 | 2,873 |
Totals | 1,877 | 1,741 | 1,591 | 5,209 |
Offspring Cohort
The Offspring Study was initiated in 1971 when the need for establishing a prospective epidemiologic study of young adults was recognized. A sample of 5,124 men and women, consisting of the offspring of the Original Cohort and their spouses was recruited. Offspring Exam 9 began in April 2011 and concluded in April of 2014.
AGE-SEX DISTRIBUTION AT ENTRY (1971) | ||||||||
---|---|---|---|---|---|---|---|---|
Age | <10 | 10-19 | 20-29 | 30-39 | 40-49 | 50-59 | 60-70 | Totals |
Men | 0 | 126 | 543 | 789 | 694 | 293 | 38 | 2,483 |
Women | 6 | 113 | 692 | 835 | 740 | 242 | 13 | 2,641 |
Totals | 6 | 239 | 1,235 | 1,624 | 1,434 | 535 | 51 | 5,124 |
Omni Cohorts 1 and 2
Omni Cohort 1
Over the years, the community of Framingham has changed. In the early 1990s, the need to establish a new group of participants reflecting the increasing diversity of the community was recognized. In 1994, the Omni Cohort 1 of the Framingham Heart Study was initiated. The original Omni cohort consisted of 507* men and women of African-American, Hispanic, Asian, Indian, Pacific Islander and Native American origins, who at the time of enrollment were residents of Framingham and the surrounding towns. Omni Cohort 1 continues to be examined and followed at the same examination cycle as the Offspring Cohort. Exam 4 for Omni Cohort 1 began in April 2011 and ended in April of 2014.
*One participant who is included in the Omni Cohort 1 did not attend Exam 1 and therefore is not represented in the table below.
OMNI COHORT 1: AGE-SEX DISTRIBUTION AT ENTRY | ||||||
---|---|---|---|---|---|---|
Age | 20-39 | 40-49 | 50-59 | 60-69 | 70-79 | Totals |
Men | 7 | 96 | 67 | 36 | 6 | 212 |
Women | 13 | 130 | 92 | 42 | 17 | 294 |
Totals | 20 | 226 | 159 | 78 | 23 | 506 |
Omni Cohort 2
In order to expand from the Omni Cohort 1 and to represent an ethnically diverse group at least 10% of the size of the Gen 3 cohort, enrollment of a second cohort of Omni participants started in 2003 and ended in July 2005. Omni Cohort 2 included many individuals related to the participants of Omni Cohort 1 and also individuals unrelated to Omni Cohort 1 members. The total attendance at the first examination cycle of Omni Cohort 2 included 410 new participants. Exam 3 for the Omni Cohort 2 started in April 2016 and is scheduled to close in 2019.
OMNI COHORT 2: AGE-SEX DISTRIBUTION AT ENTRY | |||||||
---|---|---|---|---|---|---|---|
Age | 20-29 | 30-39 | 40-49 | 50-59 | 60-69 | 70+ | Totals |
Men | 36 | 52 | 41 | 29 | 15 | 4 | 177 |
Women | 43 | 50 | 75 | 38 | 15 | 12 | 233 |
Totals | 79 | 102 | 116 | 67 | 30 | 16 | 410 |
Omni Cohort Specimens
Specimens from the two FHS Omni cohorts are now available from recent examination cycles. These samples were collected following the same protocols used for the concurrent Offspring and Third Generation examination. Exam components also follow the same protocols, starting with the first exams of each Omni Cohort. See the exam table below. The FHS encourages the use of Omni specimens in any study whenever necessary covariates are available.
OMNI COHORT SPECIMENS | |||
---|---|---|---|
Omni Cohort 1 | Offspring Cohort | Omni Cohort 2 | 3rd Generation Cohort |
Exam 1 | Exams 5 – 6 | Exam 1 | Exam 1 |
Exam 2 | Exam 7 | Exam 2 | Exam 2 |
Exam 3 | Exam 8 | ||
Exam 4 | Exam 9 |
Generation 3 (Gen 3) Cohort
A recent major component of the Framingham Heart Study protocol has been the enrollment and examination of a third generation of participants, which will provide greater resources of phenotypic and genotypic information. During Offspring Exam Cycles 6 and 7, the Offspring participants were asked to update information about their children. To assess interest in participation prior to the start of research examinations, 5,500 letters and response cards were sent in November 2001 to prospective third generation participants who had at least one parent in the Offspring Study and would be at least 20 years old by the close of the first exam cycle. Later an additional 1,241 invitation letters were sent. A prioritization of the recruitment list was prepared. Considerations were given to family size, completeness of data, stored DNA and responsiveness of the Gen III members of the families. Generation 3, Exam 1 was begun in April of 2002 and completed in July of 2005. Generation 3, Exam 2 was begun in May of 2008 and was completed in February 2011. Exam 3 started in April 2016 and is scheduled to close in 2019.
By consenting to and completing Exam 1 of Gen III, the participant was considered enrolled in the Framingham Heart Study Gen III. Special efforts were being made to complete sibships and families in the course of enrollment. A recruitment target of 4,095 Gen III participants was achieved by July of 2005. The details of research exam attendance for Gen III are described in the table to follow.
GEN3: AGE-SEX DISTRIBUTION AT ENTRY (THROUGH 2005) | ||||||||
---|---|---|---|---|---|---|---|---|
Age | 19 | 20-29 | 30-39 | 40-49 | 50-59 | 60-69 | 70-79 | Totals |
Men | 4 | 220 | 656 | 737 | 276 | 19 | 1 | 1,913 |
Women | 3 | 262 | 759 | 848 | 293 | 16 | 1 | 2,182 |
Totals | 7 | 482 | 1,415 | 1,585 | 569 | 35 | 2 | 4,095 |
New Offspring Cohort (NOS)
If the spouse of an Offspring was never enrolled in the Framingham Heart Study and if at least two of his/her biological children participated in Exam 1 of Gen III, that spouse was invited to participate in the New Offspring Spouse Exam 1. The addition of their data and cell lines may improve the statistical power for studying families at FHS. Most of the Gen III participants had both parents already enrolled in the Framingham Offspring Study. Recruitment of New Offspring Spouses (NOS) began in October 2003, and as of July 31, 2005, when the Exam 1 ended, 103 New Offspring Spouses (47 men and 56 women) had been examined. Examination 2 of the New Offspring Spouses began again in September of 2009 and ended in February 2011. Exam 3 of the NOS started in April 2016 and is scheduled to close in 2019.
NEW OFFSPRING SPOUSE COHORT: AGE-SEX DISTRIBUTION AT ENTRY (2005) | ||||||||
---|---|---|---|---|---|---|---|---|
Age | 40-49 | 50-59 | 60-69 | 70-79 | 80-89 | Totals | ||
Men | 1 | 13 | 14 | 16 | 3 | 47 | ||
Women | 1 | 19 | 17 | 17 | 2 | 56 | ||
Totals | 2 | 32 | 31 | 33 | 5 | 103 |