Table 3.
Adjusted Association of Elementary Students’ Daily Water Intake From Various School Water Sources With Experiences of School Drinking Water Security and Student Characteristics, San Francisco Bay Area, California 2017 to 2018*
| Adjusted Mean Times Per Day Students Drank Water at School | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Characteristic | Fountain (95% CI) | P Value | Sink (95% CI) | P Value | Tap Water Dispenser (95% CI) | P Value | All Tap Water Sources† (95% CI) | P Value | Bottled Water (95% CI) | P Value |
| Negative experience of water security‡ | ||||||||||
| None | Reference | Reference | Reference | Reference | Reference | |||||
| Some | −0.3 (−0.6, 0.003) | .052 | 0.1 (0.004, 0.3) | .043 | 0.1 (0.005, 0.2) | .040 | −0.04 (−0.4, 0.3) | .85 | −0.0005 (−0.2, 0.2) | .996 |
| More | −0.5 (−0.8, −0.3) | <.001 | 0.1 (−0.02, 0.2) | .092 | 0.1 (−0.003, 0.2) | .058 | −0.3 (−0.7,0.01) | .059 | 0.1 (−0.08, 0.3) | .25 |
| Age (β, 95% CI) | −0.4 (−0.7, −0.1) | .006 | −0.08 (−0.2, −0.09) | .38 | −0.1 (−0.3, −0.008) | .038 | −0.6 (−1.0,−0.2) | .002 | −0.001 (−0.2, 0.2) | .99 |
| Sex | ||||||||||
| Male | Reference | Reference | Reference | Reference | Reference | |||||
| Female | −0.5 (−0.7, −0.2) | <.001 | −0.04 (−0.2, −0.07) | .47 | −0.04 (−0.1,0.06) | .43 | −0.5 (−0.8, −0.3) | <.001 | 0.01 (−0.2, 0.2) | .90 |
| Race and ethnicity | ||||||||||
| White | Reference | Reference | Reference | Reference | Reference | |||||
| API | −0.3 (−0.8, 0.1) | .13 | 0.1 (−0.06, 0.3) | .20 | 0.1 (−0.04, 0.3) | .15 | −0.09 (−0.6, 0.4) | .73 | 0.3 (0.05, 0.6) | .019 |
| Black | 0.4 (−0.2, 1.0) | .21 | 0.008 (−0.3, 0.3) | .95 | −0.009 (−0.2, 0.2) | .92 | 0.4 (−0.3, 1.1) | .23 | 0.2 (−0.2, 0.7) | .36 |
| Latino | 0.2 (−0.2, 0.6) | .25 | 0.1 (−0.04, 0.3) | .15 | 0.07 (−0.02, 0.2) | .14 | 0.4 (0.02, 0.8) | .041 | 0.2 (−0.08, 0.4) | .19 |
| Other§ | −0.02 (−0.5, 0.4) | .93 | 0.02 (−0.2, 0.2) | .79 | 0.006 (−0.1, 0.1) | .91 | 0.01 (−0.5, 0.5) | .96 | 0.2 (−0.1, 0.5) | .21 |
| BMI z score | 0.09 (0.003, 0.2) | .043 | 0.02 (−0.03, 0.07) | .48 | 0.04 (−0.007, 0.08) | .10 | 0.1 (0.02, 0.3) | .022 | 0.03 (−0.05,0.1) | .51 |
| Intervention group | ||||||||||
| Control | Reference | Reference | Reference | Reference | Reference | |||||
| intervention | 0.2 (0.03, 0.5) | .024 | 0.1 (−0.2, 0.2) | .11 | 0.2 (0.07, 0.3) | .001 | 0.5 (0.2, 0.8) | <.001 | 0.09 (−0.08, 0.3) | .30 |
CI indicates confidence interval.
Multivariable bootstrapping linear regressions models with adjustment for student characteristics above along with student physical activity, screen time, and school intervention status were used to assess the association of daily water intake with school water security experience and student characteristics.
All tap water sources at school include fountains, sinks, and dispensers.
Cut-offs were no negative experience: score=0, some negative experience: 2 ≤ score ≤ 4, more negative experience: score ≥ 6.
Other includes participants with American Indian ancestry or 2 or more races.