Table 1.
Demographic and Clinical Characteristics of Patients in the Discovery and Validation Cohorts
| Characteristic | Discovery cohort | Validation cohort | OR or difference of means (validation vs. discovery cohort)h | |||
|---|---|---|---|---|---|---|
| No-shows (N = 107) | Attendees (N = 211) | No-shows (N = 89) | Attendees (N = 1025) | No shows | Attendees | |
| Age—mean (yrs) | 57 | 57 | 57 | 57 | −0.15 (−3.18, 2.87) | −0.69 (−2.12, 0.73) |
| Gender—% male | 51 | 49 | 54 | 47 | 0.81 (0.46, 1.42) | 0.92 (0.69, 1.24) |
| Insurance—% | ||||||
| Private | 42 | 71 | 52 | 68 | 0.68 (0.39, 1.20) | 1.15 (0.83, 1.59) |
| Medicare | 26 | 14 | 25 | 22 | 0.77 (0.36, 1.63) | 1.60 (1.04, 2.53)* |
| Mass health/medicaid/nonea | 32 | 15 | 23 | 10 | 0.60 (0.29, 1.26) | 0.71 (0.45, 1.14) |
| Education level—% | ||||||
| No more than high schoolb | 59 | 33 | 51 | 26 | 1.4 (0.80, 2.47) | 1.42 (1.04, 1.96)* |
| College or graduate schoolc | 41 | 67 | 49 | 74 | 0.71 (0.41, 1.26) | 0.70 (0.51, 0.97)* |
| Hx. colon polypsj—% | 14 | 16 | 26 | 41 | 2.14 (1.04, 4.41)* | 3.57 (2.42, 5.26)*** |
| Hx. BRBPR or (+) FOBTd,j—% | 29 | 18 | 19 | 30 | 0.58 (0.30, 1.14) | 1.93 (1.32, 2.81)*** |
| Personal Hx. CRCe,j—% | 3 | 2 | 3 | 3 | 0.83 (0.16, 4.20) | 0.71 (0.25, 2.06) |
| CRC in first degree relativee—% | 8 | 8 | 16 | 16 | 2.03 (0.83, 4.95) | 2.39 (1.40, 4.08)** |
| Hx. psychiatric illnessj—% | 53 | 34 | 52 | 42 | 0.94 (0.53, 1.65) | 1.44 (1.05, 1.96)* |
| Prior missed endoscopies—% | ||||||
| 0 | 76 | 93.4 | 98 | 99.7 | 0.08 (0.01, 0.34)i,*** | 0.04 (0.01, 0.16)i,*** |
| 1 | 9 | 5.2 | 1 | 0.3 | 13.3 (2.91, 83.8)i,*** | 24.2 (6.46, 107)i,*** |
| 2 | 6 | 1.4 | – | – | ||
| 3 | 3 | – | 1 | – | ||
| 4 | 3 | – | – | – | ||
| 5 | – | – | – | – | ||
| 6 | 1 | – | – | – | ||
| 7 | – | – | – | – | ||
| 8 | 2 | – | – | – | ||
| Mean NARf—% | 7.2 | 2 | 5.9 | 1.8 | 0.13 (−0.10, 0.35) | 0.03 (−0.03, 0.09) |
| Mean wait time—monthsg | 1.8 | 1.5 | 1.6 | 1.6 | 0.24 (−0.16, 0.64) | −0.12 (−0.33, 0.09) |
| Mean number of prior missed endoscopies | 0.6 | 0.1 | 0.04 | 0.00 | 0.54 (0.26, 0.83)*** | 0.08 (0.03, 0.12)*** |
aOne attendee from discovery cohort lacked health insurance
bCompleted grade school but no high school, some high school, and high school graduates
cCompleted some college, college graduates, and those who have attended graduate school
d BRBPR bright red blood per rectum; FOBT fecal occult blood test
e CRC colorectal cancer
f NAR non-adherence ratio
g1 month = 30 days
h p values for categorical variables are based on chi-square tests of odds ratios. p values for continuous variables are based on two-way t-tests for differences of means. Odds ratios were calculated as: odds X in discovery cohort/odds X in validation cohort
iOdds of at least one missed endoscopy in discovery cohort/odds of at least one missed endoscopy in validation cohort
jHx. = “History of”
* p < 0.05; ** P < 0.01; *** p < 0.001