Table 2.

Phase II (validation cohort) distribution of baseline variables

Individuals who underwent colonoscopy and filled some part of baseline questionnaire, by adenoma detectionIndividuals included in final analysis, by adenoma detection
Overalln = 1,450n = 1,334
N (%) or mean ± SDAdenoma detectedNo adenoma detectedAdenoma detectedNo adenoma detected
Baseline variablesn = 1,609n = 330n = 1,120n = 307n = 1,027
Age at baseline, y
 40–49137 (9%)19 (6%)94 (8%)3 (1%)8 (1%)
 50–591,110 (69%)218 (66%)788 (70%)214 (70%)781 (76%)
 60–69362 (23%)93 (28%)283 (21%)90 (29%)238 (23%)
Sex
 Male784 (49%)199 (60%)521 (47%)187 (61%)490 (48%)
 Female825 (51%)131 (40%)599 (53%)120 (39%)537 (52%)
Race
 White non-hispanic1,301 (81%)267 (81%)925 (83%)253 (82%)884 (86%)
 Other308 (19%)63 (19%)195 (17%)54 (18%)143 (14%)
Center location
 Minnesota954 (59%)209 (63%)677 (60%)205 (67%)675 (66%)
 Louisiana425 (26%)87 (26%)280 (25%)68 (22%)190 (19%)
 Washington230 (14%)34 (10%)163 (15%)34 (11%)162 (16%)
BMI
 <2034 (2%)1 (0.3%)28 (3%)1 (0.3%)25 (2%)
 20–24416 (26%)67 (20%)314 (28%)66 (22%)293 (29%)
 25–29642 (40%)141 (43%)447 (40%)133 (43%)420 (41%)
 ≥30513 (32%)118 (36%)330 (29%)107 (35%)289 (28%)
 Missing4 (0.3%)3 (0.9%)1 (0.1%)
Colorectal cancer in at least one first-degree relative
 Yes161 (10%)41 (12%)105 (9%)37 (12%)91 (9%)
 No1,437 (89%)287 (87%)1,009 (90%)270 (88%)936 (91%)
 Missing11 (0.7%)2 (0.6%)6 (0.5%)
Colorectal cancer in at least one second-degree relative
 Yes196 (12%)44 (13%)138 (12%)37 (12%)126 (12%)
 No1,402 (87%)284 (86%)976 (87%)270 (88%)901 (88%)
 Missing11 (0.7%)2 (0.6%)6 (0.5%)
Smoking
 Ever807 (50%)187 (57%)545 (49%)174 (57%)507 (49%)
 Never802 (50%)143 (43%)575 (51%)133 (43%)520 (51%)
Pack-years for ever smokers18.0 ± 18.623.1 ± 19.716.3 ± 16.822.7 ± 19.616.6 ± 17.0
Regular intake of aspirin
 Yes490 (30%)114 (34%)322 (29%)106 (35%)311 (30%)
 No1,119 (70%)216 (66%)798 (71%)201 (65%)716 (70%)
Regular intake of NSAIDS
 Yes345 (21%)67 (20%)250 (22%)60 (20%)234 (23%)
 No1,264 (79%)263 (80%)870 (78%)247 (80%)793 (77%)