Table 4 Comparison of different learning phases according to the CUSUM analysis
Variable | Total | Phase | P value | x2 | |
|---|---|---|---|---|---|
n = 184 | Learning Phase(n = 29) | Mastery Phase(n = 155) | |||
Gender |  |  |  | – | 0.804 |
Male | 104 | 17 | 87 | – | – |
Female | 80 | 12 | 68 | – | – |
Age(yr) | 65.53 ± 6.21 | 63.86 ± 6.46 | 65.84 ± 6.14 | 0.450 | – |
BMI(kg/m2) | 23.17 ± 2.45 | 23.21 ± 3.01 | 23.16 ± 2.34 | 0.138 | – |
Operation time(min) | 140.14 ± 29.13 | 175.38 ± 34.23 | 133.55 ± 22.76 | 0.002 | – |
Hospital stay(day) | 9.39 ± 2.15 | 13.07 ± 2.28 | 8.71 ± 1.23 | 0.000 | – |
Visible blood loss(ml) | 164.80 ± 18.85 | 177.89 ± 16.83 | 162.35 ± 18.24 | 0.538 | – |
Surgical failure, n(%) | 11(5.98) | 6(20.69) | 5(3.22) | – | 0.000 |
Fusion rate(n) | 92.9% (171) | 86.2% (25) | 94.2% (146) | – | 0.252 |