Table 3.

Differences between arthritis and anemia versus arthritis without anemia in length of stay, adjusted for age, sex, type of primary diagnosis of arthritis, type of secondary/associated diagnosis of arthritis, and number of associated diagnoses

		Public	Private
		Difference, days (95% CI)	Difference, days (95% CI)
Univariable analysis	Matched sample #1	0.91 (0.01 to 1.81)	0.35 (-0.67 to 1.37)
	Matched sample #2	0.68 (-0.20 to 1.56)	0.47 (-0.55 to 1.49)
	Matched sample #3	1.30 (0.47 to 2.13)	0.79 (-0.19 to 1.77)
	Matched sample #4	1.00 (0.11 to 1.89)	0.29 (-0.70 to 1.28)
	Matched sample #5	1.13 (0.28 to 1.98)	0.03 (-1.07 to 1.13)
Multivariable analysis	Whole population	1.56 (1.14 to 1.98)	0.69 (0.22 to 1.16)

Legend: Matched samples of arthritis patients with anemia and without anemia were identified based on five confounders: Sample #1 - gender (male, female); Sample #2 - age (0–59, 60–69, 70–79, 80+); Sample #3 - type of primary diagnosis of arthritis; Sample #4 - type of secondary/associated diagnosis of arthritis; Sample #5 - number of associated diagnoses/comorbidities (none, 1–2, 3–4, 5–6, 6+).