Table 1.
Sample size and characteristics of the study population, according to the NAPAIR Levelsa.
| Characteristic | No. of participants by the NAPAIR Levels (weighted %)a | P valueb | ||
|---|---|---|---|---|
| Total population |
DAP (NAPAIR 0~0.17) |
NAP (NAPAIR 0.17~1) |
||
| (N = 3,690) | (N = 1,884) | (N = 1,806) | ||
| Sex | <0.01 | |||
| Male | 1,909 (51.2) | 1,029 (52.9) | 880 (49.3) | |
| Female | 1,781 (48.8) | 855 (47.1) | 926 (50.7) | |
| Age group, y | <0.01 | |||
| 20–44 | 1,423 (43.0) | 581 (36.3) | 842 (50.2) | |
| 45–64 | 1,198 (38.6) | 615 (40.0) | 583 (37.1) | |
| ≥65 | 1,069 (18.4) | 688 (23.7) | 381 (12.7) | |
| Race/ethnicity | <0.01 | |||
| Mexican American | 585 (5.7) | 317 (5.3) | 268 (6.1) | |
| Other Hispanic | 97 (3.0) | 46 (2.8) | 51 (3.2) | |
| Non-Hispanic White | 2,053 (75.1) | 1,170 (80.3) | 883 (69.6) | |
| Non-Hispanic Black | 782 (10.4) | 278 (7.1) | 504 (13.9) | |
| Other Race | 173 (5.8) | 73 (4.5) | 100 (7.2) | |
| Education attainment | 0.55 | |||
| High school or below | 1,716 (37.7) | 886 (37.7) | 830 (37.6) | |
| College or above | 1,971 (62.3) | 997 (62.3) | 974 (62.3) | |
| Marital status | <0.01 | |||
| Married or living with a partner | 2,296 (65.7) | 1,258 (69.9) | 1,038 (61.3) | |
| Single | 1,393 (34.2) | 625 (30.0) | 768 (38.7) | |
| FPIR | <0.01 | |||
| <1.3 | 810 (14.9) | 371 (12.2) | 439 (17.8) | |
| 1.3 to <3.5 | 1,414 (36.1) | 726 (35.7) | 688 (36.6) | |
| ≥3.5 | 1,314 (45.6) | 713 (49.0) | 601 (41.9) | |
| BMI group | <0.01 | |||
| <25 | 1,172 (34.0) | 613 (33.8) | 559 (34.2) | |
| 25 to <30 | 1,330 (35.0) | 728 (37.6) | 602 (32.3) | |
| ≥30 | 1,161 (30.4) | 535 (28.2) | 626 (32.7) | |
| Health status | <0.01 | |||
| Excellent or good | 2,806 (81.4) | 1,510 (85.5) | 1,296 (77.1) | |
| Fair | 571 (11.3) | 247 (9.1) | 324 (13.6) | |
| Poor | 105 (2.2) | 41 (1.7) | 64 (2.8) | |
| Smoker | <0.01 | |||
| Current | 728 (21.3) | 316 (18.0) | 412 (24.8) | |
| Former | 1,043 (27.2) | 614 (30.5) | 429 (23.6) | |
| Never | 1,918 (51.5) | 954 (51.5) | 964 (51.6) | |
| Diabetes | 0.42 | |||
| Yes | 392 (7.8) | 188 (7.4) | 204 (8.3) | |
| No | 3,231 (90.7) | 1,663 (91.3) | 1,568 (90.0) | |
| Borderline | 64 (1.4) | 33 (1.4) | 31 (1.5) | |
| Hypertension | <0.01 | |||
| Yes | 1,595 (37.4) | 879 (40.8) | 716 (33.8) | |
| No | 2,095 (62.6) | 1,005 (59.2) | 1,090 (66.2) | |
| Hypercholesterolemia | <0.01 | |||
| Yes | 1,287 (33.3) | 738 (36.7) | 549 (29.7) | |
| No | 2,403 (66.7) | 1,146 (63.3) | 1,257 (70.3) | |
NAPAIR, Nighttime to all-day physical activity intensity ratio; NAP, nighttime active population; DAP, daytime active population; BMI, body mass index; FPIR, family poverty income ratio.
a
Weighted to be nationally representative. The weighted percentage may not sum to 100% because of missing data.
b
P values of chi-square test were calculated based on the unweighted values.