Table 3.
Results from comparison of estimated youth METs from standard, age-groups, and age-in-years models
| Activity | N | Model Descriptive Statistics |
Model Root Mean Square Error (RMSE) |
Percent Reduction in RMSE from Standard |
||||||
|---|---|---|---|---|---|---|---|---|---|---|
| All Models | Standard* | Age-Groups | Age-in-Years | Standard | Age-Groups | Age-in-Years | Age-Groups | Age-in-Years | ||
|
| ||||||||||
| Mean | (SD) | (SD) | (SD) | RMSE (RSD) | RMSE (RSD) | RMSE (RSD) | % | % | ||
| Sedentary | ||||||||||
| Computer games | 363 | 1.40 | (0.23) | (0.01) | (0.03) | 0.23 (0.31) | 0.23 (0.31) | 0.23 (0.32) | 1.59 | 0.56 |
| Television viewing | 425 | 1.20 | (0.26) | (0.05) | (0.03) | 0.26 (0.34) | 0.25 (0.33) | 0.25 (0.33) | 1.76 | 0.65 |
| Light-intensity | ||||||||||
| Housework | 233 | 3.00 | (0.57) | (0.04) | (0.05) | 0.57 (0.83) | 0.57 (0.81) | 0.57 (0.81) | −0.22 | 0.22 |
| Sweeping | 501 | 3.32 | (0.63) | (0.06) | (0.08) | 0.63 (0.79) | 0.62 (0.80) | 0.62 (0.80) | 1.22 | 0.82 |
| Wii® Play | 171 | 2.63 | (0.72) | (0.11) | (0.03) | 0.72 (1.08) | 0.70 (1.03) | 0.72 (1.08) | 1.37 | −0.23 |
| Cycling | ||||||||||
| Cycling ~10 mph | 276 | 5.76 | (1.30) | (0.43) | (0.65) | 1.29 (1.51) | 1.09 (1.31) | 1.12 (1.29) | 15.26 | 13.52 |
| Moderate- to vigorous-intensity | ||||||||||
| Aerobics | 345 | 3.83 | (0.98) | (0.21) | (0.36) | 0.98 (1.12) | 0.92 (1.06) | 0.92 (1.07) | 6.16 | 6.65 |
| Dance | 180 | 3.55 | (0.98) | (0.16) | (0.25) | 0.97 (1.23) | 0.91 (1.12) | 0.94 (1.17) | 5.68 | 3.11 |
| Walk - 2 mph | 509 | 3.56 | (0.66) | (0.23) | (0.17) | 0.66 (0.84) | 0.61 (0.77) | 0.64 (0.80) | 7.25 | 3.08 |
| Walk - 3 mph | 272 | 4.41 | (0.92) | (0.46) | (0.57) | 0.92 (1.66) | 0.92 (1.62) | 0.92 (1.64) | 0.67 | 0.41 |
| Run - 4 mph | 315 | 8.16 | (1.56) | (0.62) | (0.90) | 1.56 (1.92) | 1.22 (1.47) | 1.27 (1.61) | 21.66 | 18.25 |
| Run - 5 mph | 108 | 8.21 | (1.61) | (0.11) | (0.08) | 1.60 (2.43) | 1.53 (2.26) | 1.50 (2.21) | 4.26 | 6.51 |
| Skilled | ||||||||||
| Basketball | 263 | 6.77 | (1.63) | (0.71) | (0.91) | 1.62 (1.85) | 1.35 (1.55) | 1.35 (1.58) | 16.21 | 16.95 |
| Rope Skipping | 263 | 8.10 | (1.66) | (0.18) | 0.64) | 1.66 (2.04) | 1.50 (1.87) | 1.53 (1.85) | 8.71 | 7.60 |
*
Standard Deviation (SD) from sample, SD for model with constant is zero
Note: RMSE is the root of the mean square errors; percent reduction reflects the relative reduction in the root mean square error (RMSE) from the model that is constant across all ages compared to the models that include age. For example, percent reduction from Standard to Age-in-years is (RMSEconstant- RMSEageyrs)/RMSEconstant x 100%. Positive % indicates a decrease in error and a negative % indicates an increase in error when including age.