Table II.
Prevalence ratio and 95% confidence intervals for acne by categories of milk intake among boys in the Growing Up Today Study cohort at baseline, 1996, United States
| Servings, glasses | ≤1/wk | 2–6/wk | 1/d | ≥2/d | P value for test of trend |
|---|---|---|---|---|---|
| Milk types | |||||
| Total milk | |||||
| Cases/total | 102/176 | 356/517 | 379/523 | 1019/1543 | |
| Age-adjusted PR | 1.00 | 1.15 | 1.25 | 1.20 | .69 |
| 95% CI | 1.01, 1.32 | 1.09, 1.44 | 1.04, 1.38 | ||
| Multivariate PR | 1.00 | 1.20 | 1.22 | 1.16 | .77 |
| 95% CI | 1.03, 1.39 | 1.06, 1.41 | 1.01, 1.34 | ||
| Whole milk | |||||
| Cases/total | 99/172 | 166/242 | 172/247 | 389/618 | |
| Age adjusted PR | 1.00 | 1.20 | 1.21 | 1.09 | .91 |
| 95% CI | 1.03, 1.40 | 1.03, 1.40 | 0.95, 1.26 | ||
| Multivariate PR | 1.00 | 1.23 | 1.19 | 1.10 | .83 |
| 95% CI | 1.04, 1.46 | 1.00, 1.42 | 0.94, 1.28 | ||
| Low-fat milk | |||||
| Cases/total | 99/172 | 77/110 | 84/123 | 238/360 | |
| Age adjusted PR | 1.00 | 1.21 | 1.19 | 1.16 | .11 |
| 95% CI | 1.01, 1.45 | 1.00, 1.42 | 1.00, 1.34 | ||
| Multivariate PR | 1.32 | 1.19 | 1.17 | .08 | |
| 95% CI | 1.05, 1.67 | 0.94, 1.51 | 0.99, 1.39 | ||
| Skim milk | |||||
| Cases/total | 99/172 | 97/147 | 110/136 | 381/551 | |
| Age adjusted PR | 1.00 | 1.15 | 1.37 | 1.21 | .01 |
| 95% CI | 0.97, 1.37 | 1.18, 1.60 | 1.05, 1.39 | ||
| Multivariate PR | 1.00 | 1.12 | 1.29 | 1.19 | .02 |
| 95% CI | 0.90, 1.39 | 1.08, 1.54 | 1.01, 1.40 | ||
Multivariate PR of acne for categories of intakes adjusted for age, height, and energy intake.
CI, Confidence interval; PR, prevalence ratio.