Table 6.

Risk factors for failure to respond at 2 years of follow-up in 633 patients

Factors	OR a, b	95% CI	p-value	OR c	95% CI	p-value
Only received postal questionnaires at 2 years d	3.2	(2.1–4.9)	< 0.001	3.2	(2.1–4.9)	< 0.001
Age	0.99	(0.97–1.0)	0.05	0.98	(0.97–1.0)	0.05
Had any complication	0.23	(0.54–1.0)	0.05	0.26	(0.06–1.1)	0.07
Days of hospital stay	0.89	(0.82–0.96)	0.01	0.99	(0.90–1.1)	0.9
Health state	1.0	(0.99–1.0)	0.1
Living alone	1.3	(0.89–2.0)	0.2

^a OR: odds ratio.

^b Univariate analysis.

^c Multivariate analysis.

^d Protocol A, operated in 2000 and 2001.