Table 3.
Interobserver reliability tested with intraclass correlation coefficient (ICC), Kappa Index, and Cronbach's alpha for the 2D and 3D measurements
| Interobserver reliability | Intraclass correlation coefficient (ICC) | K index | Cronbach’s alpha | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Single measures | CI 95% | Average measures | CI95% | Obs 1 (T1) and Obs 2 (T1)Kappa | SD | CI 95% | Obs 1 (T1) and Obs 2 (T1) Alpha | CI 95% | |
| 2D measurements | |||||||||
| Transepicondylar distance (TD) | 0.9878 | 0.9786–0.9931 | 0.9939 | 0.9892–0.9965 | 0.864 | 0.019 | 0.827–0.902 | 0.9939 | 0.9902 |
| Medial femoral condyle AP dimension | 0.877 | 0.7929–0.9283 | 0.9344 | 0.8845–0.9628 | 0.677 | 0.049 | 0.580–0.774 | 0.9369 | 0.8986 |
| Lateral femoral condyle AP dimension | 0.8882 | 0.8110–0.9300 | 0.9408 | 0.8956–0.9664 | 0.772 | 0.042 | 0.490–0.853 | 0.9427 | 0.9079 |
| Proximal tibia ML dimension | 0.9788 | 0.9630–0.9879 | 0.9893 | 0.9811–0.9939 | 0.858 | 0.02 | 0.820–0.897 | 0.9894 | 0.9829 |
| Medial tibial plateau AP dimension | 0.8533 | 0.7552–0.9140 | 0.9208 | 0.8605–0.9551 | 0.535 | 0.062 | 0.414–0.657 | 0.9291 | 0.8861 |
| Lateral tibial plateau AP dimension | 0.8955 | 0.8228–0.9393 | 0.9448 | 0.9028–0.8687 | 0.647 | 0.038 | 0.572–0.723 | 0.9449 | 0.9114 |
| Tibial PCL insertion-trochlearcartilage distance | 0.9406 | 0.8977–0.9659 | 0.9694 | 0.9461–0.9826 | 0.724 | 0.041 | 0.0645–0.804 | 0.9694 | 0.9509 |
| Patellar tendon length | 0.7314 | 0.5706–0.8381 | 0.8448 | 0.7266–0.9119 | 0.515 | 0.067 | 0.383–0.647 | 0.8603 | 0.7754 |
| 3D measurements | |||||||||
| Intrarticular length of ACL graft | 0.771 | 0.6379–0.8671 | 0.8745 | 0.7789–0.928 | 0.535 | 0.066 | 0.405–0.664 | 0.8770 | 0.8022 |
| Outside-in femoral tunnel length | 0.8475 | 0.7461–0.9105 | 0.9175 | 0.8546–0.9532 | 0.457 | 0.053 | 0.354–0.560 | 0.9175 | 0.8674 |
| Outside-in anatomic ACL reconstruction | 0.9121 | 0.8501–0.9491 | 0.954 | 0.9190–0.9739 | 0.585 | 0.048 | 0.492–0.678 | 0.9590 | 0.9340 |
| Saragaglia/Yamaguchi techniques | 0.8267 | 0.7136–0.8978 | 0.9051 | 0.8329–0.9462 | 0.619 | 0.059 | 0.503–0.735 | 0.9053 | 0.8477 |
| Anatomic anterolateral ligament reconstruction | 0.4244 | 0.1682–0.6270 | 0.5959 | 0.2880–0.7707 | 0.271 | 0.071 | 0.131–0.410 | 0.5967 | 0.3517 |
| Lateral extrarticular tenodesis (anatomical femur) | 0.6268 | 0.4242–0.7696 | 0.7706 | 0.5957–0.8698 | 0.342 | 0.066 | 0.213–0.470 | 0.798 | 0.6753 |
| Lateral extrarticular tenodesis (non-anatomical femur) | 0.8831 | 0.8028–0.9319 | 0.9379 | 0.8906–0.9648 | 0.638 | 0.047 | 0.546–0.730 | 0.9396 | 0.9030 |
| Over the top femoral position ACL reconstruction | 0.8517 | 0.7526–0.9131 | 0.9199 | 0.8589–0.9545 | 0.641 | 0.047 | 0.546–0.730 | 0.9218 | 0.8743 |
| Marcacci technique | 0.8831 | 0.8028–0.9319 | 0.9379 | 0.8906–0.9648 | 0.638 | 0.047 | 0.546–0.730 | 0.9396 | 0.9030 |
The second measurement (T1) of each observer was used for every test
CI Confidence interval, AP anteroposterior, ML mediolateral, PCL posterior cruciate ligament, ACL anterior cruciate ligament