Table 3

Impact of LOS on PROMs.

PROMLOS ≥45 h,
Mean ± SD
LOS <45 h,
Mean ± SD
P Valuea
VAS back
 Preoperative6.5 ± 2.36.7 ± 2.60.673
 6 wk4.3 ± 2.73.8 ± 2.50.257
 12 wk4.0 ± 2.63.3 ± 2.60.212
 6 mo3.0 ± 2.63.4 ± 2.80.511
 1 y3.0 ± 3.52.1 ± 3.00.657
 2 y8.5 ± 0.06.4 ± 1.60.377
VAS leg
 Preoperative5.1 ± 2.74.5 ± 3.40.813
 6 wk4.5 ± 4.33.3 ± 2.40.263
 12 wk3.2 ± 2.82.5 ± 2.60.662
 6 mo2.0 ± 2.62.6 ± 3.10.613
 1 y2.2 ± 3.71.1 ± 1.70.489
 2 y6.5 ± 0.06.3 ± 2.60.964
ODI
 Preoperative39.4 ± 17.535.7 ± 15.80.477
 6 wk45.1 ± 32.528.3 ± 14.8 0.024
 12 wk29.3 ± 16.120.3 ± 12.40.082
 6 mo22.3 ± 20.220.2 ± 15.80.739
 1 y30.5 ± 24.214.9 ± 16.20.153
 2 y40.0 ± 0.028.5 ± 13.70.507
SF-12 PCS
 Preoperative27.1 ± 6.332.6 ± 9.5 0.046
 6 wk34.0 ± 11.834.8 ± 8.40.838
 12 wk32.2 ± 5.141.5 ± 8.7 0.014
 6 mo40.3 ± 8.140.0 ± 9.50.920
 1 y37.6 ± 9.145.9 ± 11.00.193
 2 y36.2 ± 2.544.6 ± 11.80.271
PROMIS-PF
 Preoperative34.4 ± 5.038.4 ± 5.80.072
 6 wk40.8 ± 2.640.0 ± 5.90.847
 12 wk40.2 ± 4.644.6 ± 9.20.271
 6 mo43.0 ± 7.247.2 ± 6.50.199
 1 y44.0 ± 9.148.7 ± 11.00.411
 2 y47.2 ± 9.049.6 ± 12.20.823
  • Abbreviations: LOS, length of stay; ODI, Oswestry Disability Index; PROMIS-PF, patient-reported outcome measurement information system physical function; PROMs, patient-reported outcome measures; SF-12 PCS, 12-item short form physical composite score; VAS, visual analog scale.

  • Note: Boldface indicates statistical significance.

  • a P values calculated using Student’s t test for independent samples.