Table 1.

Dropout analysis comparing elderly and younger patients with complete and missing postoperative data in SweSpine regarding age, gender, level operated, VAS as an estimation of back and leg pain, SF-36 as an estimation of quality of life, and ODI as an estimation of disability. Elderly is defined as those aged ≥65 years, and younger refers to the sex-matched comparison group aged 20–64

	Elderly			Younger
	Included	Lost to 1 year	p-value	Included	Lost to 1 year	p-value
	n = 1,250	n = 418		n = 12,840	n = 5,273
Age, mean (SD)	71 (5.2)	73 (6.7)	< 0.001	43 (10)	41 (10)	< 0.001
Men/women, %	53/47	42/58	< 0.001	55/45	60/40	< 0.001
Operated level
L4–L5, %	53	53	0.2	41	41	0.2
L5–S1, %	20	22		53	53
VAS back paina	53 (51–55)	55 (52–59)	0.2	46 (46–47)	48 (47–49)	0.02
VAS leg paina	69 (67–70)	65 (62–68)	0.03	66 (66–67)	66 (65–66)	0.4
SF-36 PCSa	37 (36–38)	35 (33–36)	0.008	37 (36–37)	35 (35–36)	< 0.001
SF-36 MCSa	28 (28–29)	28 (27–29)	0.4	31 (31–32)	31 (30–31)	< 0.001
ODI-indexa	50 (49–51)	51 (49–53)	0.5	48 (48–49)	49 (48–49)	0.2

^amean (95% CI)