F Test P Values Comparing Compartment Models Based on Population Average
| Model | Tumor | Muscle | Brain |
| 2-tissue model vs. 1-tissue model | <0.0001 | <0.0001 | <0.0001 |
| Reversible vs. irreversible 2-tissue model | >0.05 | >0.05 | >0.05 |
Reversible (fitted k4), irreversible (k4 = 0). A P value of ≤ 0.05 indicates that the model with more parameters yielded a better fit to the data.