Table 4.

Differences in median (interquartile range) gap and step-off measurements between more-experienced and less-experienced observers.

	More-experienced observers	Less-experienced observers	P-value
Preoperative gap
Radiographs	6.3 (1.9–10.7) mm	7.7 (1.9–14.2) mm	0.003
CT scans	17.5 (10.5–28.9) mm	19.5 (11.3–26.0) mm	0.080
Preoperative step-off
Radiographs	6.3 (0.6–18.1) mm	3.7 (0–8.7) mm	0.000
CT scans	9.0 (3.5–13.9) mm	9.5 (5.3–15.0) mm	0.024
Postoperative gap
Radiographs	0.0 (0.0–2.3) mm	2.9 (2.9–4.4) mm	0.000
CT scans	3.5 (2.1–5.5) mm	8.0 (6.0–10.0) mm	0.000
Postoperative step-off
Radiographs	0.0 (0.0–0.0) mm	0.0 (0.0–0.0) mm	0.823
CT scans	1.0 (0.0–2.4) mm	4.0 (1.3–5.8) mm	0.000

P ≤ 0.05 was considered statistically significant.