Table 2.
Demographic and Clinical Characteristics of the Entire Sample (mean±sd, unless noted otherwise) and Split Based on MPH Treatment Status (mean±se, unless noted otherwise)
| Entire Sample n=194 |
No-MPH n=40 |
MPH-Cont n=91 |
MPH-Intermit N=63 |
Statistic | p-value | |
|---|---|---|---|---|---|---|
| Age, yrs | 11.7±2.8 | 12.9±0.4 | 12.1±0.3 | 10.4±0.3 | F=11.93 | <0.0001 |
| Tanner Stage (%) | ||||||
| I/II/III/IV/V | 39/16/14/18/12 | 56/19/10/8/6 | 33/17/14/27/9 | 25/10/23/15/28 | χ2= 28.87 | 0.0003 |
| Race/Ethnicity, n (%) | Fisher’s Exact |
>0.10 | ||||
| White | 161 (84) | 36 (90) | 73 (81) | 52 (84) | ||
| African American | 23 (12) | 1 (3) | 15 (17) | 7 (11) | ||
| Hispanic | 5 (3) | 2 (5) | 1 (1) | 2 (3) | ||
| Other | 3 (2) | 1 (3) | 1 (1) | 1 (2) | ||
| Height Z-score¶ | ||||||
| At Baseline (n=126) | 0.28±1.02 | 0.57±0.18 | 0.21±0.14 | 0.17±0.16 | F=1.63 | >0.20 |
| At Study Entry | 0.19±0.96 | 0.70±0.15 | 0.06±0.10 | 0.05±0.12 | F=7.60 | 0.0007 |
| Change (n=126) | −0.05±0.65 | 0.11±0.12 | −0.15±0.09 | −0.05±0.10 | F=1.52 | >0.20 |
| BMI Z-score¶ | 0.55±1.00 | 0.62±0.16 | 0.42±0.10 | 0.69±0.13 | F=1.53 | >0.20 |
| Physical Activity | 2.4±1.1 | 2.1±0.2 | 2.6±0.1 | 2.5±0.1 | F=1.94 | >0.10 |
| Daily Calcium, mg | 1011±376 | 1007±60 | 1011±42 | 1015±50 | F=0.01 | >0.90 |
| Daily Vitamin D, IU | 274±152 | 254±24 | 267±17 | 299±20 | F=1.21 | >0.30 |
MPH: psychostimulants.
¶
Age-sex-specific height and body mass index (BMI) Z-scores generated based on the 2000 Centers for Disease Control and Prevention normative data. Baseline height measurements were collected within 90 days before or 15 days after the initiation of psychostimulants. For the No-MPH group, height measurements obtained at a date preceding study entry by an interval comparable to that in the other two MPH groups were selected (see Methods).
Significant results (p<0.05) are bolded and marginally significant results (p<0.10) are bolded and italicized.