Table 5.

Postoperative physical function and pain over predetermined time periods.

PROM	PHQ-9 <5 (n = 186)	PHQ-95–10 (n = 94)	PHQ-9>10 (n = 71)	P valuea
PROMIS-PF
Preoperative	38.8 ± 7.1 (149)	35.6 ± 6.9 (67)	33.3 ± 5.9 (51)	<0.001
6 wk	44.4 ± 8.3 (112)	41.2 ± 8.1 (52)	38.9 ± 8.7 (36)	0.001
12 wk	47.8 ± 9.7 (69)	43.5 ± 8.3 (39)	42.5 ± 9.7 (21)	0.018
6 mo	46.3 ± 8.6 (56)	42.3 ±10.0 (32)	40.2 ± 12.7 (20)	0.036
1 y	45.3 ± 10.0 (38)	44.9 ± 12.9 (22)	43.4 ± 11.3 (18)	0.836
VAS back
Preoperative	5.7 ± 2.6 (170)	6.6 ± 2.7 (86)	7.0 ± 2.0 (65)	<0.001
6 wk	2.5 ± 2.4 (131)	2.8 ± 2.7 (63)	3.6 ± 2.9 (55)	0.024
12 wk	2.2 ± 2.4 (56)	3.1 ± 2.7 (42)	4.1 ± 2.7 (29)	0.009
6 mo	2.7 ± 2.5 (40)	4.2 ± 3.4 (32)	5.0 ± 3.1 (22)	0.011
1 y	3.8 ± 3.2 (17)	3.4 ± 3.3 (16)	5.0 ± 2.6 (12)	0.412
VAS leg
Preoperative	5.7 ± 2.6 (170)	6.3 ± 2.9 (86)	6.8 ± 2.4 (65)	0.009
6 wk	2.3 ± 2.5 (131)	2.7 ± 2.8 (63)	3.7 ± 2.9 (55)	0.009
12 wk	2.5 ± 2.6 (57)	2.7 ± 2.8 (42)	3.8 ± 3.2 (29)	0.110
6 mo	2.4 ± 2.5 (40)	3.3 ± 3.0 (32)	4.7 ± 3.3 (22)	0.017
1 y	2.4 ± 3.0 (17)	2.8 ± 2.8 (16)	4.5 ± 3.6 (12)	0.180

Data presented as mean ± SD (n).

aP value was calculated using linear regression.

PHQ-9, Patient Health Questionnaire-9; PROMIS-PF, Patient-Reported Outcomes Measurement Information System Physical Function; VAS, visual analog scale.