Table 4. Smoking-Attributable Fraction (SAF) of Health Care Utilization by Type of Health Services, Smoking Status, and Age Group, 2020.

Cigarette smoking status	SAF, %a
	Inpatient care	ED visits	Physician visits	Home health visits
Aged 35-64 y
Current smokers	13.7	6.6	4.9	15.5
Former smokers	5.3	2.6	2.2	5.9
<15 y	4.6	2.3	1.9	5.1
≥15 y	0.7	0.3	0.3	0.8
All smokers	19.0	9.2	7.1	22.4
Age ≥65 y
Current smokers	3.9	2.7	1.6	3.3
Former smokers	4.2	3.0	1.8	4.2
<15 y	4.2	3.0	1.8	4.2
≥15 y	0.0b	0.0	0.0	0.0b
All smokers	8.1	5.7	3.4	7.5

Abbreviation: ED, emergency department.

^a Derived based on the estimated econometric models shown in eTable 2 in Supplement 1 and the 2020 cigarette smoking prevalence rates shown in Table 3.

^b The original SAF values that were calculated based on the estimated econometric model were −1.9%, −1.3%, −0.8%, and −2.4% for inpatient care, ED visits, physician visits, and home health visits, respectively. Because a negative SAF suggests that former smokers possess a reduced morbidity risk compared with never smokers, which is against the evidence linking smoking and health, we assume that these SAFs are 0.