| for some uses | 6 | purpose |
| relatively | 5 | degree |
| at their proximal end | 3 | location |
| catheter → be → stiff | 15 |
| catheter → have → variable stiffness | 4 |
| catheter → include → stiffness characteristics | 3 |
| catheter → have → sufficient stiffness | 3 |
| negative | neutral | positive |
| 0.168 | 0.693 | 0.139 |
| Raw frequency | 25 |
| Normalized frequency | 0.353 |
| Modifier score | 0.500 |
| Perplexity | 383.214 |