| Duration of Exposure to PCMH By Treatment Arm | ||||||
|---|---|---|---|---|---|---|
| ≤4 Months | >4 and <8 Months | ≥8 Months | ||||
| UC (n = 351) | Intervention (n = 1048) | UC (n = 316) | Intervention (n = 935) | UC (n = 499) | Intervention (n = 1515) | |
| Primary outcome | ||||||
| Any CRCS | ||||||
| Unadjusted percentage (95% CI) | 36.8 (31.9–41.9) | 70.7 (67.9–73.4) | 34.8 (29.7–40.2) | 69.3 (66.3–72.2) | 44.9 (40.6–49.3) | 66.1 (63.6–68.4) |
| SOS intervention effect | ||||||
| Adjusted RR† (95% CI) | 1.0 (Referent) | 1.98 (1.79–2.17) | 1.0 (Referent) | 1.96 (1.62–3.42) | 1.0 (Referent) | 1.49 (1.34–1.63) |
| Adjusted difference‡ (95% CI) | Referent | 34.4 (30.6–38.2) | Referent | 34.1 (27.4–40.8) | Referent | 21.9 (17.4–26.4) |
| Secondary outcomes | ||||||
| Any fecal test§ | ||||||
| Unadjusted percentage (95% CI) | 21.1 (17.1–25.7) | 63.8 (60.9–66.7) | 20.6 (16.5–25.4) | 61.8 (58.7–64.9) | 32.7 (28.7–36.9) | 58.0 (55.4–60.4) |
| SOS intervention effect | ||||||
| Adjusted RR† (95% CI) | 1.0 (Referent) | 3.05 (2.48–3.62) | 1.0 (Referent) | 2.98 (2.20–3.76) | 1.0 (Referent) | 1.80 (1.51–2.09) |
| Adjusted difference‡ (95% CI) | Referent | 42.2 (37.6–46.9) | Referent | 41.2 (36.0–46.3) | Referent | 26.2 (20.9–31.5) |
| Any endoscopy | ||||||
| Unadjusted percentage (95% CI) | 21.4 (17.4–26.0) | 20.7 (18.4–23.3) | 20.6 (16.5–25.4) | 19.4 (16.9–22.0) | 18.2 (15.1–21.9) | 17.0 (15.2–19.0) |
| SOS intervention effect | ||||||
| Adjusted RR† (95% CI) | 1.0 (Referent) | 1.00 (0.86–1.14) | 1.0 (Referent) | 0.92 (0.64–1.21) | 1.0 (Referent) | 0.93 (0.79–1.08) |
| Adjusted difference‡ (95% CI) | Referent | 0.0 (−2.8 to 2.8) | Referent | −1.6 (−8.0 to 4.8) | Referent | −1.2 (−4.2 to 1.7) |
Interaction P value to test for differences in Systems of Support to Increase Colorectal Cancer Screening Trial (SOS) intervention effects by level of exposure to a patient-centered medical home: P < .01 for any colorectal cancer screening (CRCS) and fecal test; P = .49 for any endoscopy.
↵* CRCS tests included completion of fecal occult blood tests, flexible sigmoidoscopy, or colonoscopy during year one of the SOS trial. All patients were overdue for CRCS.
↵† RR = Relative Risk of CRCS testing in SOS intervention group relative to SOS usual care group, adjusted for age, sex, race, education, and prior testing.
↵‡ Adjusted difference = percent tested in SOS intervention group relative to SOS usual care group, adjusted for age, sex, race, education, and prior CRC tests.
↵§ Hemoccult SENSA.
CI, confidence interval; PCMH, patient-centered medical home; UC, usual care.