Table 3.
| Usual Care N=1163 |
Intervention N=3490 |
P-value e | |
|---|---|---|---|
|
| |||
| Year 1 | |||
| Eligible for screening, N | 1163 | 3490 | |
| Fecal test | 299 (25.7) | 2112 (60.5) | <0.001 |
| Flexible sigmoidoscopy c | 52 (4.5) | 169 (4.8) | |
| Colonoscopy | 175 (15.1) | 481 (13.8) | 0.32 |
| Any testing | 457 (39.3) | 2379 (68.2) | <0.001 |
| Censored during year 1 d, n | 78 | 225 | |
|
| |||
| Year 2 | |||
| Eligible for screening, N | 870 | 2642 | |
| Fecal test | 177 (20.3) | 1389 (52.6) | <0.001 |
| Flexible sigmoidoscopy | 7 (0.8) | 24 (0.9) | |
| Colonoscopy | 109 (12.5) | 284 (10.8) | 0.16 |
| Any testing | 278 (32.0) | 1597 (60.5) | <0.001 |
| Censored during year 2, n | 46 | 165 | |
|
| |||
| Year 3 | |||
| Eligible for screening, N | 712 | 2179 | |
| Fecal test | 193 (27.1) | 830 (38.1) | <0.001 |
| Flexible sigmoidoscopy | 0 (0.0) | 7 (0.3) | |
| Colonoscopy | 60 (8.4) | 167 (7.7) | 0.44 |
| Any testing | 244 (34.3) | 966 (44.3) | <0.001 |
| Censored during year 3, n | 62 | 186 | |
|
| |||
| Year 4 | |||
| Eligible for screening, N | 593 | 1828 | |
| Fecal test | 198 (33.4) | 695 (38.0) | 0.11 |
| Flexible sigmoidoscopy | 2 (0.3) | 4 (0.2) | |
| Colonoscopy | 44 (7.4) | 134 (7.3) | 0.73 |
| Any testing | 237 (40.0) | 792 (43.3) | 0.35 |
| Censored during year 4, n | 43 | 97 | |
|
| |||
| Year 5 | |||
| Eligible for screening, N | 504 | 1601 | |
| Fecal test | 231 (45.8) | 875 (54.7) | <0.001 |
| Flexible sigmoidoscopy | 0 (0.0) | 5 (0.3) | |
| Colonoscopy | 28 (5.6) | 98 (6.1) | 0.62 |
| Any testing | 248 (49.2) | 940 (58.7) | <0.001 |
| Censored during year 5, n | 36 | 138 | |
If a participant had a combination of fecal tests, flexible sigmoidoscopy, or colonoscopy, fecal test is only counted if it is the first test. Sigmoidoscopy and colonoscopy always count unless both occur, in which case only the first of these is counted.
Eligible for screening in a year if had not received a flexible sigmoidoscopy or colonoscopy, or been censored in a prior year. In a given year, a participant may have both a colonoscopy, flexible sigmoidoscopy, and be censored.
Intervention effects on completion of flexible sigmoidoscopy by year was not tested, due to low participation rates
Participants with a diagnosis of CRC, those who died, reached age 76 or disenrolled from the health plan were censored.
P-Values from separate Poisson models with follow-up time as offset parameter, adjusted for age, sex, race, and education for each year and type of test amongst those eligible for screening in a given year.