Table 2.
Spline mixed models investigating the association between new child package dose and WHZ growth trajectories1
| Slope differences (SE) | Mean WHZ differences (SE) | |||||
|---|---|---|---|---|---|---|
| Years of new child package received | Age (years) | Boys | Girls | Age (years) | Boys | Girls |
| < 1 year vs. 0 years | 0 to 0.5 | 0.04 (0.10) | 0.06 (0.10) | 0 | 0.06 (0.03) | 0.02 (0.03) |
| 0.5 to 1 | − 0.07 (0.09) | − 0.05 (0.09) | 0.5 | 0.08 (0.03)* | 0.05 (0.03) | |
| 1 to 1.5 | −0.14 (0.08) | − 0.22 (0.08)** | 1 | 0.04 (0.03) | 0.03 (0.03) | |
| 1.5 to 2 | 0.23 (0.06)*** | 0.18 (0.06)** | 1.5 | −0.03 (0.03) | −0.08 (0.03) | |
| to 3 | −0.02 (0.02) | 0.02 (0.02) | 2 | 0.09 (0.03)*** | 0.00 (0.03) | |
| 3 to 4 | −0.05 (0.02)* | − 0.03 (0.02) | 3 | 0.06 (0.02)** | 0.03 (0.02) | |
| 4 to 5 | 0.01 (0.04) | −0.05 (0.04) | 4 | 0.02 (0.02) | 0.00 (0.02) | |
| 5 | 0.03 (0.04) | −0.05 (0.03) | ||||
| 1 to <2 years vs 0 years | 0 to 0.5 | −0.01 (0.10) | − 0.05 (0.10) | 0 | 0.09 (0.03)** | 0.04 (0.04) |
| 0.5 to 1 | − 0.10 (0.09) | −0.05 (0.09) | 0.5 | 0.09 (0.03)** | 0.02 (0.03) | |
| 1 to 1.5 | −0.03 (0.08) | − 0.02 (0.08) | 1 | 0.04 (0.03) | −0.01 (0.03) | |
| 1.5 to 2 | 0.09 (0.06) | 0.07 (0.06) | 1.5 | 0.02 (0.03) | −0.02 (0.03) | |
| 2 to 3 | −0.04 (0.02) | −0.03 (0.02) | 2 | 0.07 (0.03)** | 0.02 (0.03) | |
| 3 to 4 | 0.00 (0.02) | −0.02 (0.02) | 3 | 0.03 (0.02) | −0.01 (0.02) | |
| 4 to 5 | −0.02 (0.04) | −0.03 (0.04) | 4 | 0.03 (0.02) | −0.03 (0.02) | |
| 5 | 0.00 (0.04) | −0.06 (0.03) | ||||
| 2 to < 3 years vs. 0 years | 0 to 0.5 | 0.05 (0.10) | 0.20 (0.10) | 0 | 0.07 (0.03)* | −0.01 (0.03) |
| 0.5 to 1 | −0.11 (0.09) | − 0.14 (0.09) | 0.5 | 0.09 (0.03)** | 0.09 (0.03) | |
| 1 to 1.5 | 0.00 (0.08) | −0.12 (0.08) | 1 | 0.04 (0.03) | 0.02 (0.03) | |
| 1.5 to 2 | −0.06 (0.06) | 0.04 (0.06) | 1.5 | 0.04 (0.03) | −0.04 (0.03) | |
| 2 to 3 | −0.04 (0.02) | 0.02 (0.02) | 2 | 0.01 (0.03) | −0.02 (0.03) | |
| 3 to 4 | 0.00 (0.02) | −0.02 (0.02) | 3 | −0.04 (0.02) | 0.00 (0.02) | |
| 4 to 5 | 0.01 (0.04) | −0.02 (0.04) | 4 | −0.04 (0.02) | −0.02 (0.02) | |
| 5 | −0.02 (0.04) | −0.04 (0.03) | ||||
| 3 to < 4 years vs. 0 years | 0 to 0.5 | 0.23 (0.09)* | 0.17 (0.09) | 0 | 0.02 (0.03) | 0.03 (0.03) |
| 0.5 to 1 | −0.05 (0.08) | −0.08 (0.08) | 0.5 | 0.13 (0.03)*** | 0.12 (0.03) | |
| 1 to 1.5 | −0.24 (0.08)** | −0.25 (0.07)*** | 1 | 0.11 (0.03)*** | 0.08 (0.03) | |
| 1.5 to 2 | 0.21 (0.06)*** | 0.14 (0.06)* | 1.5 | −0.01 (0.03) | −0.05 (0.03) | |
| 2 to 3 | −0.09 (0.02)*** | 0.00 (0.02) | 2 | 0.09 (0.03) | 0.02 (0.03) | |
| 3 to 4 | −0.01 (0.02) | −0.01 (0.02) | 3 | 0.01 (0.02) | 0.02 (0.02) | |
| 4 to 5 | −0.01 (0.04) | −0.04 (0.04) | 4 | 0.00 (0.02) | 0.01 (0.02) | |
| 5 | −0.02 (0.03) | −0.03 (0.03) | ||||
| 4 years vs. 0 years | 0 to 0.5 | 0.07 (0.08) | 0.12 (0.08) | 0 | −0.05 (0.03) | −0.06 (0.03)* |
| 0.5 to 1 | −0.06 (0.07) | −0.16 (0.07) | 0.5 | −0.01 (0.02) | 0.00 (0.02) | |
| 1 to 1.5 | −0.08 (0.06) | −0.02 (0.06) | 1 | −0.04 (0.02) | − 0.08 (0.02)*** | |
| 1.5 to 2 | 0.12 (0.05)* | 0.10 (0.05)* | 1.5 | −0.08 (0.02)*** | −0.09 (0.02)*** | |
| 2 to 3 | −0.05 (0.02)** | −0.02 (0.02) | 2 | −0.02 (0.02) | − 0.04 (0.02)* | |
| 3 to 4 | −0.02 (0.02) | −0.02 (0.02) | 3 | −0.06 (0.02)*** | − 0.06 (0.02)** | |
| 4 to 5 | −0.01 (0.03) | 0.01 (0.03) | 4 | −0.09 (0.02)*** | −0.08 (0.02)*** | |
| 5 | −0.10 (0.03)*** | −0.07 (0.03)* | ||||
1Gender-stratified piecewise linear spline mixed models based on a sample of fully formula fed children 0–4 years participating in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) in Los Angeles County, California, 2003–2016
* < 0.05 ** < 0.01 *** < 0.001
Abbreviations: SE standard error; WIC Special Supplemental Nutrition Program for Women, Infants and Children; WHZ weight-for-height z-score