Table 3

Multivariate Models Assessing Factors Associated With Primary Care Physicians’ Ordering of Lung Cancer Screening Tests

Factor	Ordered Chest Radiograph OR (95% CI)	Ordered LDCT OR (95% CI)
Physician characteristics
Years since graduation from medical school
<10	1.0	1.0
10–19	1.2 (0.7–2.3)	1.7 (0.9–3.3)
20–29	2.2 (1.2–4.1)^a	3.0 (1.5–5.9)^a
≥30	1.5 (0.8–3.0)	2.5 (1.3–5.0)
Sex
Male	1.0	1.0
Female	1.2 (0.8–1.8)	0.8 (0.5–1.4)
Specialty
Family medicine/general practice	1.0	1.0
General internal medicine	1.2 (0.8–1.7)	1.6 (1.1–2.4)^a
Board certified
Yes	1.0	1.0
No	0.8 (0.5–1.3)	0.9 (0.6–1.5)
Practice characteristics
Primary practice arrangement
Full/part owner of practice	1.6 (1.0–2.3)	1.4 (0.9–2.1)
Employee or other/missing	1.0	1.0
Practice size (number of physicians)
1	1.0	1.0
2–5	0.1 (0.7–1.7)	1.5 (0.9–2.5)
6–15	1.4 (0.8–2.4)	1.9 (1.1–3.3)^a
≥16/missing	0.6 (0.3–1.1)	1.3 (0.7–2.7)
Census region
Northeast	1.0	1.0
Midwest	0.7 (0.5–1.2)	0.8 (0.5–1.4)
West	1.0 (0.6–1.6)	0.8 (0.5–1.5)
South	0.8 (0.5–1.4)	0.6 (0.3–1.0)
Type of health record system used
Full EHR	1.0	1.0
Partial EHR	0.7 (0.4–1.2)	0.9 (0.4–2.0)
Transitioning from paper to EHR	1.2 (0.7–2.1)	0.6 (0.3–1.1)
Paper charts/missing	1.1 (0.7–1.7)	0.8 (0.4–1.4)
Patients who are uninsured, %
0–5	1.0	1.0
6–25	0.9 (0.6–1.4)	1.0 (0.6–1.5)
≥26/don’t know/missing	0.5 (0.3–1.0)	0.6 (0.3–1.1)
Physician beliefs
Believes any expert group recommends lung cancer screening
No	1.0	1.0
Yes	1.7 (1.1–2.9)^a	1.8 (1.2–2.8)^a
Believes LDCT is effective for
Never, former, and current smokers (all 3)	–	8.2 (3.3–20.6)^a
Never, former, or current smokers	–	6.0 (2.3–15.8)^a
No patients	–	1.0
Physician practice style
Patient volume during a typical week
≤75	1.0	1.0
76–100	1.7 (1.1–2.7)^a	1.1 (0.7–1.9)
101–125	1.6 (1.0–2.6)	1.0 (0.6–1.8)
≥126/missing	1.1 (0.7–1.8)	1.5 (0.8–3.0)
Intensity of colorectal cancer screening recommendations
Low/moderate	1.0	1.0
High	1.0 (0.6–1.4)	0.7 (0.5–1.1)
Unknown	1.3 (0.5–3.1)	0.9 (0.4–1.8)
Types of patients for whom physician recommends lung cancer screening
All, regardless of smoking exposure	14.6 (7.0–30.4)^a	2.1 (1.1–4.0)^a
Any smoking exposure, active or passive	4.6 (3.1–6.8)^a	2.9 (1.7–5.0)^a
Current and/or former smokers only	2.4 (1.5–4.0)^a	2.4 (1.4–4.2)^a
None	1.0	1.0
Patient influence
Number of patients who have asked about lung cancer screening in past 12 months
0	1.0	1.0
1–5	2.7 (1.8–3.9)^a	1.8 (1.1–3.0)^a
6–10	2.9 (1.9–4.6)^a	2.0 (1.1–3.5)^a
>10	5.3 (3.2–8.8)^a	3.2 (1.9–5.6)^a
Unknown	1.3 (0.2–8.4)	1.7 (0.4–7.4)

EHR = electronic health record; LDCT = low-dose spiral computed tomography; OR = odds ratio.
Note: Race/ethnicity, geographic location, and medical school affiliation were not included in the models because these measures were not statistically significant in bivariate analyses at P <.10.
↵a Indicate a statistically significant odds ratio.