Table 4.

Differences between arthritis and anemia versus arthritis without anemia in number of procedures, 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, no of procedures (95% CI)	Difference, no of procedures (95% CI)
Univariable analysis	Matched sample #1	0.58 (0.29 to 0.87)	0.17 (-0.16 to 0.50)
	Matched sample #2	0.48 (0.20 to 0.76)	-0.12 (-0.46 to 0.22)
	Matched sample #3	0.45 (0.17 to 0.73)	0.14 (-0.20 to 0.48)
	Matched sample #4	0.44 (0.16 to 0.72)	0.02 (-0.32 to 0.36)
	Matched sample #5	0.45 (0.18 to 0.72)	0.17 (-0.17 to 0.51)
Multivariable analysis	Whole population	0.52 (0.38 to 0.65)	0.08 (-0.11 to 0.27)

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+).