Between enrollment and 1998-1999 (Year 11), participants were seen in the clinic annually and contacted by phone at 6-month intervals. For more details, see the summary & frequency of types of clinic visit data collected.
From 1999 to 2023, participants were contacted every 6 months by phone, primarily to ascertain health status for events follow-up.
In 2005-2006 (Year 18), CHS participants in the CHS All Stars Study were seen in person or by phone to assess physical and cognitive function.
In 2018-2019 (Year 31), CHS participants were seen in-person or contacted by phone to assess physical and cognitive function.
CHS Schedule of Annual Visits* 1989-2023
CHS Year |
Calendar Year |
Type of visit |
# participating |
2 (baseline) |
1989-90 |
In-person |
5,201 |
3 |
1990-91 |
In-person |
4,972 |
4 |
1991-92 |
In-person |
4,799 |
5 (baseline for supplementary cohort) |
1992-93 |
In-person |
5,265 |
6 |
1993-94 |
In-person |
5,057 |
7 |
1994-95 |
In-person |
4,842 |
8 |
1995-96 |
In-person |
4,662 |
9 |
1996-97 |
In-person |
4,413 |
10 |
1997-98 |
In-person |
4,249 |
11 |
1998-99 |
In-person |
3,964 |
12 |
1999-00 |
Phone |
3,519 |
13 |
2000-01 |
Phone |
3,084 |
14 |
2001-02 |
Phone |
3,052 |
15 |
2002-03 |
Phone |
2,779 |
16 |
2003-04 |
Phone |
2,481 |
17 |
2004-05 |
Phone |
2,244 |
18 (All-Stars) |
2005-06 |
In-person & Phone |
1,904 - Total 1,143 - In-person |
19 |
2006-07 |
Phone |
1,826 |
20 |
2007-08 |
Phone |
1,656 |
21 |
2008-09 |
Phone |
1,421 |
22 |
2009-10 |
Phone |
1,267 |
23 |
2010-11 |
Phone |
1,099 |
24 |
2011-12 |
Phone |
920 |
25 |
2012-13 |
Phone |
756 |
26 |
2013-14 |
Phone |
617 |
27 |
2014-15 |
Phone |
470 |
28 |
2015-16 |
Phone |
408 |
29 |
2016-17 |
Phone |
287 |
30 |
2017-18 |
Phone |
207 |
31 |
2018-19 |
In-person & Phone |
47 - In-person 83 - Phone |
32 |
2019-20 |
Phone |
76 |
33 |
2020-21 |
Phone |
66 |
34 |
2021-22 |
Phone |
42 |
35 |
2022-23 |
Phone |
20 |
*annual visits only are shown; 6-month visits occur between annual visits and are phone-only
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