The most recent dataset available is version 4.2, this includes the main survey interview data up to Survey 9, all the CAMDEX interview data and retrospective informant interview data. All data have been double-entered and cleaned. Dates of death are up-dated to 22/09/2012.
Tables and explanatory notes for general use of the dataset
- Details numbers in each survey
- General audit trail of the 2610 individuals in baseline screen
- Audit trail of the 2610 individuals (Participant only) in baseline screen
Table 1 below details the numbers of participants in each survey who were interviewed in person and for whom a proxy informant was interviewed instead or as well:
Details of numbers in each survey
|
Surveys |
Only study participant interviewed |
Both participant and ≥ 1 proxy informant interviewed separately |
P articipant and proxy informant interviewed together |
Total number of participants interviewed in person |
1 proxy informant interviewed |
> 1 proxy informant interviewed |
Proxy informant data only |
Interviewer assessment of participant but only proxy informant interviewed |
Total in survey (Participant or proxy informant) |
Total number of interviews |
|
Survey1(Year0) |
2610 |
0 |
0 |
2610 |
0 |
0 |
0 |
0 |
2610 |
2610 |
|
Survey1(Year0)_SFU |
2166 |
0 |
0 |
2166 |
0 |
0 |
0 |
0 |
2166 |
2166 |
|
Survey1A |
332 |
0 |
0 |
332 |
0 |
0 |
0 |
0 |
332 |
332 |
|
Survey2(Year2) |
1156 |
0 |
21 |
1177 |
0 |
0 |
0 |
0 |
1177 |
1177 |
|
Survey3(Year7) |
648 |
27 |
3 |
678 |
61 |
1 |
35 |
13 |
713 |
741 |
|
Survey4(Year10) |
368 |
34 |
3 |
405 |
75 |
0 |
41 |
8 |
446 |
480 |
|
Survey5(Year13) |
177 |
19 |
2 |
198 |
52 |
2 |
35 |
1 |
233 |
254 |
|
Survey6(Year17) |
73 |
24 |
2 |
99 |
35 |
0 |
11 |
0 |
110 |
134 |
|
Survey7(Year21) |
6 |
21 |
10 |
37 |
28 |
1 |
7 |
0 |
44 |
66 |
|
Survey8(Year23) |
2 |
9 |
0 |
11 |
9 |
0 |
0 |
0 |
11 |
20 |
|
Survey9(Year25) |
1 |
3 |
2 |
6 |
4 |
0 |
1 |
0 |
7 |
10 |
|
CAMDEX1.1(Year0) |
530 |
0 |
0 |
530 |
0 |
0 |
0 |
0 |
530 |
530 |
|
CAMDEX1.2(Year2) |
217 |
0 |
0 |
217 |
0 |
0 |
0 |
0 |
217 |
217 |
|
CAMDEX1.3(Year3) |
152 |
0 |
0 |
152 |
0 |
0 |
0 |
0 |
152 |
152 |
|
CAMDEX2.1(Year3) |
463 |
0 |
0 |
463 |
0 |
0 |
0 |
0 |
463 |
463 |
|
CAMDEX2.2(Year5) |
300 |
0 |
0 |
300 |
0 |
0 |
0 |
0 |
300 |
300 |
|
CAMDEX3.1(Year8) |
125 |
0 |
0 |
125 |
0 |
0 |
0 |
0 |
125 |
125 |
Note: The Survey1Year0 of 2610 people, 2166 individuals form the baseline sample for the longitudinal cohort which excluded one of the original general practices (444 individuals) because of differential recruitment and a sub-group involved in a branch study.
Table 2 below provides a general audit trail showing sources of attrition between surveys:
General audit trail of the 2610 individuals in the original survey
|
Survey |
Participant number in each survey1 |
Participants dropping out of the study |
Participants re-joining the study |
| Survey 1 Year 0 | 2610 | 1 Participant was transferred to other study, but re-attended the study at CAMDEX 3.1, Survey 4 and Survey 5. | |
| Transfer to other study (Chesterton Study) | 444 | ||
| Survey1 Year 0_SFU | 2166 | ||
| Died | 309 | ||
| Too ill | 29 | ||
| Refused | 189 | ||
| Moved | 56 | ||
| Not approached | 381 | ||
| Other reason not join in follow up interview | 22 | ||
| Survey 2 Year 2 | 1180 2 | ||
| Died | 373 | ||
| Too ill | 18 | ||
| Refused | 104 | ||
| Moved | 4 | ||
| Other reason not join in follow up interview | 16 | ||
| Survey 3 year 7 | 713 | 25 participants missed the Survey 2 interview, but took part in Survey 3.6 missed the Survey 2 interview, but only proxy re-joined Survey 3 interview. | |
| Proxy only interviews | 23 | ||
| Survey 3 Participant interviews |
690 | ||
| Died | 237 | ||
| Too ill | 12 | ||
| Refused | 26 | ||
| Moved | 9 | ||
| Other reason not join in follow up interview | 31 | ||
| Survey 4 Year 10 | 446 | 38 participants missed one of the previous interviews, but re-joined study at Survey 4. | |
| Proxy only interviews | 33 | ||
| Survey 4 Participant interviews | 413 | ||
| Died | 171 | ||
| Too ill | 4 | ||
| Refused | 25 | ||
| Other reason not join in follow up interview | 27 | ||
| Survey 5 Year 13 | 233 | 13 participants missed one of the previous interviews, but re-joined the study at Survey 5.5 missed at least one previous survey, but only proxy re-joined for Survey 5. | |
| Proxy only interviews | 36 3 | ||
| Survey 5 Participant interviews | 199 | ||
| Died | 122 | ||
| Too ill | 1 | ||
| Refused | 2 | ||
| Moved | 1 | ||
| Other reason not join in follow up interview | 7 | ||
| Survey 6 Year 17 | 110 | 33 participants missed one of the previous interviews, but re-joined the study at Survey 6. 4 missed at least one previous survey, but only proxy re-joined for Survey 6. |
|
| Proxy only interviews | 11 | ||
| Survey 6 Participant interviews | 99 | ||
| Died | 61 | ||
| Too ill | 3 | ||
| Refused | 2 | ||
| Survey 7 Year 21 | 44 | 4 participants missed one of the previous interviews, but re-joined the study at Survey 7. | |
| Proxy only interviews | 7 | ||
| Survey 7 Participant interviews | 37 | ||
| Died | 61 | ||
| Too ill | 3 | ||
| Refused | 2 | ||
| Survey 8 Year 23 | 11 | ||
| Proxy only interviews | 0 | ||
| Survey 8 Participant interviews | 11 | ||
| Died | 23 | ||
| Not approached | 10 | ||
| Survey 9 Year 25 | 7 | 3 participants missed one of the previous interviews, but re-joined the study at Survey 9.1 missed at least one previous survey, but only proxy re-joined for Survey 9. | |
| Proxy only interviews | 1 | ||
| Survey 9 Participant interviews | 6 | ||
| Died | 8 |
1. Number in each survey includes participant only interviews, and proxy only interviews if there is no participant interview.2.
2. The number includes 3 participants who were in the study, but having the weird records contain no data, dropped from database, so n=1177 in Survey 2 database.
3 The number includes 2 interviews with 2 proxies.
Table 3 below provides a participant only audit trail showing sources of attrition between surveys:
Audit trail of the 2610 individuals (participant only) in the original survey
|
Survey |
Number in each survey1 |
Participants dropping out of the study |
Participants re-joining the study |
| Survey 1 Year 0 | 2610 | 1 Participant was transferred to other study, but re-attended the study at CAMDEX 3.1, Survey 4 and Survey 5. | |
| Transfer to other study (Chesterton Study) | 444 | ||
| Survey1 Year 0_SFU | 2166 | ||
| Died | 309 | ||
| Too ill | 29 | ||
| Refused | 189 | ||
| Moved | 56 | ||
| Not approached | 381 | ||
| Other reason not join in follow up interview | 22 | ||
| Survey 2 Year 2 | 1180 2 | ||
| Died | 373 | ||
| Too ill | 18 | ||
| Refused | 104 | ||
| Moved | 4 | ||
| Other reason not join in follow up interview | 16 | ||
| Survey 3 year 7 | 690 | 25 participants missed the Survey 2 interview, but took part in Survey 3. | |
| Died | 237 | ||
| Too ill | 12 | ||
| Refused | 26 | ||
| Moved | 9 | ||
| Other reason not join in follow up interview | 31 | ||
| Survey 4 Year 10 | 413 | 38 participants missed one of the previous interviews, but re-joined study at Survey 4. | |
| Died | 171 | ||
| Too ill | 4 | ||
| Refused | 25 | ||
| Other reason not join in follow up interview | 27 | ||
| Survey 5 Year 13 | 199 | 13 participants missed one of the previous interviews, but re-joined the study at Survey 5. | |
| Died | 122 | ||
| Too ill | 1 | ||
| Refused | 2 | ||
| Moved | 1 | ||
| Other reason not join in follow up interview | 7 | ||
| Survey 6 Year 17 | 99 | 33 participants missed one of the previous interviews, but re-joined the study at Survey 6. | |
| Died | 61 | ||
| Too ill | 3 | ||
| Refused | 2 | ||
| Survey 7 Year 21 | 37 | 4 participants missed one of the previous interviews, but re-joined the study at Survey 7. | |
| Died | 61 | ||
| Too ill | 3 | ||
| Refused | 2 | ||
| Survey 8 Year 23 | 11 | ||
| Died | 23 | ||
| Not approached | 10 | ||
| Survey 9 Year 25 | 6 | 3 participants missed one of the previous interviews, but re-joined the study at Survey 9.1 missed at least one previous survey, but only proxy re-joined for Survey 9. | |
| Died | 8 |
1. Number in each survey includes participant only interviews, participant and >=1 proxy interviews, and proxy interviews with interviewer assessment on participant.
2. The number includes 3 participants who were in the study, but having the weird records contain no data, dropped from database, so n=1177 in Survey 2 database