Table 2 Distribution of length of stay for each categorical variable
Variables | Length of stay | p-valuea | |
|---|---|---|---|
Mean | ±SD | ||
Inpatient-level variables | |||
Sex | |||
Male | 26.28 | ±22.39 | 0.2594 |
Female | 23.83 | ±18.96 | |
Age | |||
Less than median (≤52) | 23.50 | ±20.66 | 0.0011 |
More than median (>52) | 28.37 | ±22.58 | |
Principal diagnosis (ICD-10) | |||
Cervical disc disorders (M50) | 15.54 | ±12.28 | <.0001 |
Fracture of neck (S12) | 25.03 | ±20.21 | |
Dislocation, sprain and strain of joints and ligaments at neck level (S13) | 22.66 | ±19.80 | |
Injury of nerves and spinal cord at neck level (S14) | 32.51 | ±23.20 | |
Others | 31.32 | ±25.78 | |
Cervical spine surgery performed with cervical discectomy | |||
None | 17.27 | ±13.87 | 0.0049 |
Arthrodesis | 25.65 | ±21.72 | |
Corpectomy or corpectomy + arthrodesis | 34.26 | ±23.55 | |
Charlson Comorbidity Index | |||
0 | 21.22 | ±18.73 | <.0001 |
1 | 24.87 | ±22.50 | |
2 | 28.36 | ±20.22 | |
≤ 3 | 33.14 | ±24.50 | |
Other surgical procedures during hospitalization | |||
Not received | 20.95 | ±18.76 | <.0001 |
Received | 32.09 | ±23.62 | |
Study period | |||
2014, January-June | 28.67 | ±23.62 | 0.0795 |
2014, July-December | 25.15 | ±22.62 | |
2015, January-June | 24.14 | ±19.30 | |
2015, July-December | 24.16 | ±19.97 | |
Hospital-level variables (cut-offs denote the median values) | |||
Proportion of inpatients with automobile insurance (%) | |||
≤ 2.8% | 23.09 | ±19.90 | 0.0016 |
> 2.8% | 28.09 | ±23.14 | |
Volume of invasive cervical discectomy | |||
≤ 20.0 | 27.57 | ±21.43 | 0.0096 |
> 20.0 | 23.71 | ±21.83 | |
Bed turnover rate | |||
≤ 31.8 | 28.59 | ±23.59 | <.0001 |
> 31.8 | 22.80 | ±19.12 | |
Number of neurosurgeons/orthopedic specialists per 100 beds | |||
≤ 2.2 | 28.24 | ±24.18 | 0.0025 |
> 2.2 | 23.63 | ±19.11 | |
Number of beds | |||
≤ 833 | 28.26 | ±21.15 | 0.0007 |
> 833 | 23.21 | ±21.97 | |
Types of hospital | |||
Clinic or hospital (N = 40) | 20.06 | ±15.52 | 0.0646 |
General hospital (N = 118) | 26.12 | ±22.00 | |
Area | |||
Metropolitan (N = 154) | 24.74 | ±21.97 | 0.0007 |
Non-metropolitan (N = 71) | 28.34 | ±20.80 | |
Total | 25.75 | ±21.69 | |