Table 1.
Psychometric properties. Proportion of correct answers, loglinear Rasch model fit, and differential item functioning (DIF) in the 30-item CTG test
| Item | Blueprint domain | Pilot test participants Proportion of correct answers in percent n = 118 |
CTG course participants Proportion of correct answers in percent n = 1679 |
Loglinear Rasch | DIF | ||
|---|---|---|---|---|---|---|---|
| Observed | Expected | P-value | P-value | ||||
| Item1 | Indication | 81.4 | 97.7 | 0.350 | 0.346 | - | * |
| Item2 | Classification | 78.8 | 91.8 | 0.737 | 0.685 | - | - |
| Item3 | Classification | 82.2 | 92.9 | 0.795 | 0.751 | - | - |
| Item4 | Classification | 80.5 | 97.0 | 0.524 | 0.530 | - | - |
| Item5 | Equipment | 94.1 | 99.3 | 0.134 | 0.348 | - | - |
| Item6 | Management | 94.1 | 99.5 | 0.537 | 0.348 | - | - |
| Item7 | Indication | 74.6 | 93.9 | 0.466 | 0.372 | - | * |
| Item8 | Classification | 73.3 | 89.7 | 0.296 | 0.341 | - | * |
| Item9 | Classification | 57.6 | 70.0 | 0.153 | 0.242 | - | - |
| Item10 | Management | 86.4 | 92.1 | 0.278 | 0.342 | - | - |
| Item11 | Physiology | 72.9 | 95.6 | 0.371 | 0.345 | - | - |
| Item12 | Physiology | 80.5 | 96.7 | 0.633 | 0.414 | - | - |
| Item13 | Classification | 72.9 | 96.4 | 0.583 | 0.610 | - | - |
| Item14 | Management | 83.1 | 97.3 | 0.636 | 0.704 | - | - |
| Item15 | Management | 85.6 | 97.1 | 0.440 | 0.346 | - | - |
| Item16 | Physiology | 76.3 | 96.3 | 0.331 | 0.345 | - | - |
| Item17 | Physiology | 93.2 | 97.3 | 0.160 | 0.346 | - | - |
| Item18 | Physiology | 72.0 | 85.0 | 0.327 | 0.338 | - | + |
| Item19 | Physiology | 80.2 | 96.8 | 0.442 | 0.416 | - | + |
| Item20 | Classification | 77.1 | 95.7 | 0.724 | 0.646 | - | - |
| Item21 | Classification | 82.2 | 94.9 | 0.572 | 0.596 | - | - |
| Item22 | Physiology | 91.5 | 98.5 | 0.615 | 0.517 | - | - |
| Item23 | Management | 87.3 | 98.5 | 0.608 | 0.546 | - | - |
| Item24 | Management | 88.1 | 98.5 | 0.552 | 0.347 | - | - |
| Item25 | Classification | 71.2 | 93.5 | 0.481 | 0.451 | - | + |
| Item26 | Physiology | 60.2 | 98.5 | 0.445 | 0.347 | - | - |
| Item27 | Management | 93.2 | 96.9 | 0.479 | 0.346 | - | - |
| Item28 | Management | 66.1 | 79.0 | 0.159 | 0.218 | - | *+ |
| Item29 | Classification | 66.9 | 91.5 | 0.543 | 0.466 | - | - |
| Item30 | Management | 74.6 | 98.9 | 0.723 | 0.500 | - | - |
- Non-significant P-values
* P-values that indicate DIF concerning profession
+ P-values that indicate DIF concerning regions