Table 3.

Associations of Physician Continuity and Clinic Continuity With ED and Hospital Use, by Patient Complexity^{^a}

Characteristic	ED Visits, Incidence Rate Ratio (95% CI)			Hospitalizations, Incidence Rate Ratio (95% CI)
Characteristic	Low Complexity	Moderate Complexity	High Complexity	Low Complexity	Moderate Complexity	High Complexity
Physician continuity^{^b}	1.00 (1.00-1.00)	1.00 (1.00-1.00)	1.00 (1.00-1.00)	1.00 (1.00-1.00)	1.00 (1.00-1.00)	1.00 (1.00-1.00)
Clinic continuity^{^c}
NA	0.81 (0.80-0.81)	0.79 (0.78-0.81)	0.68 (0.67-0.70)	0.77 (0.75-0.78)	0.67 (0.66-0.68)	0.78 (0.76-0.79)
None	Ref	Ref	Ref	Ref	Ref	Ref
Low	1.04 (1.03-1.06)	1.05 (1.04-1.07)	1.04 (1.02-1.06)	1.12 (1.10-1.14)	1.11 (1.07-1.15)	1.10 (1.08-1.13)
High	0.94 (0.93-0.95)	0.97 (0.95-0.99)	0.94 (0.92-0.95)	0.97 (0.95-0.98)	1.02 (0.99-1.06)	0.97 (0.95-0.99)
Complete	0.79 (0.78-0.80)	0.81 (0.80-0.83)	0.72 (0.71-0.73)	0.77 (0.75-0.78)	0.83 (0.80-0.86)	0.69 (0.67-0.70)
Sex, male	1.10 (1.09-1.11)	0.98 (0.97-1.00)	1.07 (1.06-1.08)	0.86 (0.84-0.89)	1.01 (1.01-1.01)	1.03 (1.01-1.05)
Age, per 5 years	0.98 (0.98-0.98)	1.00 (0.99-1.00)	1.00 (1.00-1.00)	0.93 (0.93-0.93)	1.01 (1.03-1.14)	1.03 (1.03-1.04)
Total visits, per visit	1.05 (1.05-1.05)	1.03 (1.03-1.03)	1.02 (1.02-1.02)	1.05 (1.05-1.05)	1.02 (1.02-1.02)	1.02 (1.02-1.02)
Physician visit volume, per patient/day	1.00 (1.00-1.00)	1.00 (1.00-1.00)	1.00 (1.00-1.00)	1.00 (1.00-1.00)	1.00 (1.00-1.00)	1.00 (1.00-1.00)
Location
Metro	Ref	Ref	Ref	Ref	Ref	Ref
Urban	1.41 (1.39-1.42)	1.44 (1.42-1.47)	1.28 (1.26-1.30)	1.41 (1.38-1.43)	1.36 (1.31-1.40)	1.35 (1.32-1.38)
Rural	2.68 (2.66-2.70)	2.46 (2.42-2.50)	2.33 (2.30-2.36)	1.76 (1.73-1.78)	1.65 (1.60-1.69)	1.74 (1.70-1.77)

CRG = clinical risk grouper; ED = emergency department; FP = family physician; GCR = group care rate; KPC = known provider of care; NA = not applicable; Ref = reference group.
Note: Adjusted for sex, age, visits in study period, average physician patient volume per day, and location.
↵a Based on CRG. Low = 1-2; moderate = 3-4; high = 5-9.
↵b Per 1% increase in KPC index.
↵c Based on GCR; see Table 1 footnotes for category definitions.