Predictive Value of Age in MTR Measurements of GM and WM
| Measurements | Rediction Equation | R2 |
|---|---|---|
| GM Mean | Mean = 29.1 + 0.067 × Age − 0.001 × Age2 | 49.10% |
| GM Median (%) | Median = 29.9 + 0.097 × Age − 0.001 × Age2 | 44.60% |
| GM First Quartile (%) | First Quartile = 27.3 + 0.072 × Age − 0.001 × Age2 | 55.30% |
| GM Peak HT (×10−3) | HT = 111.5 − 0.389 × Age | 34.90% |
| WM Mean | Mean = 32.4 + 0.066 × Age − 0.001 × Age2 | 42.80% |
| WM Median (%) | Median = 33.5 + 0.069 × Age − 0.001 × Age2 | 32.20% |
| WM First Quartile (%) | First Quartile = 31.4 + 0.071 × Age − 0.001 × Age2 | 48.80% |
| WM Peak HT (×10−3) | HT = 166.5 − 0.561 × Age | 32.50% |
Note.—Peak HT represents normalized peak height of magnetization transfer ratio histogram. R2 is associated with the prediction model and represents the percentage of the total variance of the magnetization transfer ratio measure that is explained by its association (either linear or quadratic) with age.