Table 2.

Linear Regression Model Coefficients, With Standard Errors andP Values for Predicting One-Year Change in BMI (kg/m2) in Girls and Boys

FactorOne-Year Change in BMI Predicted by Diet and Activity
In Year Before Initial BMIMean Over Two YearsYear-to-Year ChangeIn the Year Between the Two BMIs
β (Standard Error [β])Pβ (Standard Error [β])Pβ (Standard Error [β])Pβ (Standard Error [β])P
Girls
 Calories (100 kcal/d)+.0028  (.0026).293+.0056  (.0029).053+.0059  (.0027).028.0061  (.0026).016
 Fat (g/d)+.0012  (.0015).421+.0011  (.0018).537+.0004  (.0016).792+.0008  (.0016).632
 Fiber (g/d)+.0023  (.0041).577+.0026  (.0048).582−.0031  (.0043).465+.0011  (.0043).799
 Gym classes (number/wk)−.0056  (.0111).615−.0082  (.0123).508−.0088  (.0094).352−.0067  (.0098).496
 Activity (excluding gym, h/d)−.0100  (.0137).469−.0229  (.0157).144−.0262  (.0136).054−.0284  (.0142).046
 TV/video/games (h/d)+.0193  (.0081).018+.0380  (.0106).001+.0053  (.0083).526+.0372  (.0106).001
Boys
 Calories (100 kcal/d)−.0038  (.0028).178+.0013  (.0031).661+.0082  (.0030).006.0032  (.0028).249
 Fat (g/d)−.0018  (.0018).296−.0017  (.0019).377+.0010  (.0018).577−.0015  (.0017).375
 Fiber (g/d)−.0059  (.0045).186−.0045  (.0051).373+.0025  (.0049).610−.0046  (.0047).320
 Gym classes (number/wk)−.0300  (.0133).025−.0031  (.0147).830+.0407  (.0119).001+.0185  (.0121).128
 Activity (excluding gym, h/d)−.0090  (.0151).550−.0188  (.0170).267−.0113  (.0149).448−.0261  (.0156).094
 TV/videos/games (h/d)+.0265  (.0085).002+.0425  (.0104).001−.0019  (.0086).830+.0384  (.0101).001
  • * The 6 factors above were in the model simultaneously along with race, menarche history (girls), annual height growth, baseline BMI, age, and Tanner stage. Fat and fiber were energy-adjusted. Gym class measures participation at the time of BMI measurement, not past year.