Table 3.

Sequential outcomes of the study population during 2 years of follow-up

Follow-up	3 months		12 months		2 years
n (response rate)	598 (95%)		574 (91%)		629 (99%) a
EQ-5D score b	0.45 (0.41–0.48)	< 0.001	0.46 (0.43–0.50)	< 0.001	0.46 (0.43–0.49)	< 0.001
Health state b	29 (27–31)	< 0.001	31 (29–34)	< 0.001	30 (28–32)	< 0.001
Leg pain b	43 (41–46)	< 0.001	41 (38–44)	< 0.001	41 (38–44)	< 0.001
Back pain b	29 (27–31)	< 0.001	28 (25–31)	< 0.001	27 (24–30)	< 0.001
Benefited from the operation, n (%) c	539 (90)		527 (92)		571 (91)
Received worker's compensation, n (%) d	335 (57)		166 (31)		181 (29)

^a Includes non-respondents interviewed by telephone.

^b Absolute values (improvements from baseline) are shown as mean change, (95% CI) and p-value

^c Patients who stated that they had “some”, “much”, or “very much” benefit from the operation.

^d Patients who were on full or partial sick leave, on rehabilitation, or disability pensioners.