Table 1 Demographic characteristics of the analyzed sample and the excluded sample
Characteristic | Final sample (N = 5819) | Excluded (N = 4595) | P valuea |
|---|---|---|---|
Age, mean (SD), years | 11.9 (0.6) | 12.1 (0.7) |  < 0·001 |
Sex | Â | Â | 0.046 |
 Male | 3098 (53.2) | 2355 (51.3) |  |
 Female | 2721 (46.8) | 2240 (48.7) |  |
Race/ethnicity |  |  |  < 0·001 |
 Non-Hispanic White | 3347 (57.5) | 2255 (49.1) |  |
 Non-Hispanic Black | 643 (11.1) | 779 (17.0) |  |
 Hispanic | 1122 (19.3) | 964 (21.0) |  |
 Asian | 128 ( 2.2) | 88 ( 1.9) |  |
 Other | 579 (10.0) | 509 (11.1) |  |
Household married |  |  |  < 0·001 |
 Married | 4141 (71.2) | 3044 (66.2) |  |
 Unmarried | 1678 (28.8) | 1485 (32.8) |  |
Household income | Â | Â | 0.093 |
 < 50 k | 1590 (27.3) | 1097 (29.1) |  |
 ≥ 50 k and < 100 k | 1718 (29.5) | 1051 (27.9) |  |
 ≥ 100 k | 2511 (43.2) | 1618 (43.0) |  |
Parental highest attained education levelb |  |  < 0·001 | |
 Below High School | 211 ( 3.6) | 252 ( 5.5) |  |
 High School Grad/GED | 423 ( 7.3) | 487 (10.6) |  |
 Some College | 1412 (24.3) | 1208 (26.4) |  |
 Bachelor Degree | 1596 (27.4) | 1146 (25.0) |  |
 Postgraduate Degree | 2177 (37.4) | 1490 (32.5) |  |
BMI, mean (SD) | 20.59 (4.84) | 20.56 (4.90) | 0.811 |