Table 3.

Multinomial regression analysis presenting odds ratios for reporting 1–2 pain sites or ≥3 pain sites at follow-up, stratified by no pain or 1–2 pain sites at baseline

		1–2 pain sites		≥3 pain sites
		OR	95% CI	OR	95% CI
No pain	Model 1a
	Sleep Ab	1
	Sleep Bc	1.43	0.71–2.89	2.19	0.65–7.31
	Sleep Cd	0.80	0.31–2.06	4.86*	1.47–16.02
	Model 2e
	Sleep Ab	1		1
	Sleep Bc	1.44	0.71–2.92	2.24	0.65–7.70
	Sleep Cd	0.81	0.31–2.11	5.27*	1.52–18.23
	Model 3f
	Sleep Ab	1		1
	Sleep Bc	1.43	0.70–2.90	2.31	0.66–8.09
	Sleep Cd	0.90	0.34–2.40	4.55*	1.28–16.12
Pain from 1–2 sites	Model 1a
	Sleep Ab	1		1
	Sleep Bc	1.29	0.77–2.17	1.53	0.85–2.73
	Sleep Cd	0.92	0.53–1.59	1.98*	1.11–3.52
	Model 2e
	Sleep Ab	1		1
	Sleep Bc	1.30	0.77–2.19	1.54	0.86–2.77
	Sleep Cd	0.91	0.52–1.58	1.90*	1.10–3.39
	Model 3g
	Sleep Ab	1
	Sleep Bc	1.31	0.78–2.21	1.55	0.86–2.79
	Sleep Cd	0.93	0.53–1.62	1.94*	1.08–3.49

CI, confidence interval; OR, odds ratio.

^*Significant result at the 0.05 level.

^aCrude.

^bBest sleep.

^cMedium sleep

^dWorst sleep

^eAdjusted for age and gender.

^fAdjusted for age, gender and body mass index.

^gAdjusted for age, gender and inclusion as case or referent.