Table 2.

Univariable associations.

Univariable analysis	Persistent back pain			Persistent disability			Perceived nonrecovery
Candidate predictors	OR*	95% CI	P	OR*	95% CI	P	OR*	95% CI	P
Age (y)	1.04	1.02–1.06	0.000	1.05	1.03–1.08	0.000	1.04	1.02–1.06	0.001
Gender, male	0.60	0.43–0.84	0.003	0.68	0.49–0.93	0.015	0.64	0.46–0.89	0.008
Chronic duration (>3 mo)	3.40	2.27–5.08	0.000	3.02	1.97–4.62	0.000	3.16	2.09–4.80	0.000
Back pain intensity in the past wk (NRS 0-10)	1.29	1.21–1.38	0.000	1.27	1.19–1.36	0.000	1.20	1.12–1.27	0.000
Disability (RMDQ 0-24)	1.14	1.11–1.18	0.000	1.25	1.21–1.30	0.000	1.11	1.08–1.14	0.000
Recent episode of back pain (previous 6 mo)	4.20	2.81–6.26	0.000	3.70	2.54–5.38	0.000	5.58	3.70–8.42	0.000
Musculoskeletal comorbidity	2.45	1.64–3.67	0.000	2.75	1.83–4.12	0.000	2.12	1.43–3.14	0.000
Referred pain to the leg	1.98	1.44–2.73	0.000	2.31	1.67–3.19	0.000	1.62	1.18–2.24	0.003
Spinal morning stiffness (>30 min)	3.71	2.48–5.54	0.000	4.65	2.98–7.27	0.000	2.54	1.73–3.73	0.000
Pain during spinal rotation	2.53	1.80–3.56	0.000	2.32	1.65–3.27	0.000	2.03	1.44–2.86	0.000
Patients' expectation to recover	0.32	0.23–0.45	0.000	0.35	0.25–0.48	0.000	0.25	0.18–0.36	0.000
Depressive symptomatology (CES-D 0-60)	1.07	1.05–1.10	0.000	1.11	1.08–1.14	0.000	1.05	1.02–1.07	0.000
Kinesiophobia (FABQ-PA 0-28)	1.08	1.05–1.12	0.000	1.11	1.08–1.14	0.000	1.07	1.04–1.10	0.000
Pain catastrophizing (PCS 0-52)	1.04	1.02–1.06	0.000	1.07	1.05–1.09	0.000	1.03	1.02–1.05	0.000

^*Pooled estimates from the univariable regression analysis in the imputed data sets.