Missing Millions · 2026 estimate

California is missing 1,104,700 lung cancer screenings.

About 1 in 11 adults ages 50 to 80 in California qualifies for lung cancer screening and hasn't been screened. Find your county below.

1,327,800adults qualify for screening under USPSTF 2021 criteria (estimate)
16.8%were screened, 32nd of 51 (American Lung Association, 2025); 18.2% nationally
21,576low-dose CT screening scans billed to Medicare fee-for-service by California providers in 2024

Sources: U.S. Census Bureau Population Estimates 2025; CDC PLACES 2025; USPSTF 2021; American Lung Association, State of Lung Cancer 2025; CMS Medicare Physician and Other Practitioners 2024 (CPT 71271). Modeled estimates; see methodology below.

The gap, county by county

Shade shows how many adults ages 50 to 80 are missing screening. Select a county.

Los Angeles County

284,200

missing lung cancer screenings (estimate)

  • Qualify for screening341,600
  • Adults 50 to 80 missing screening1 in 11
  • Medicare low-dose CT scans, 20245,864
Open the Los Angeles County page

Every California county, ranked

Ranked by estimated missing screenings. Select a column to sort.
1Los Angeles County284,200341,6001 in 115,864
2San Diego County82,90099,7001 in 122,544
3Orange County79,90096,0001 in 131,029
4Riverside County74,20089,2001 in 11181
5San Bernardino County64,80077,9001 in 10219
6Sacramento County47,70057,3001 in 101,363
7Alameda County39,10047,0001 in 13333
8Santa Clara County38,90046,7001 in 151,718
9Contra Costa County30,20036,3001 in 13941
10Fresno County29,90035,9001 in 9166
11Kern County29,00034,9001 in 8239
12Ventura County24,30029,2001 in 12399
13San Joaquin County24,20029,1001 in 1052
14San Francisco County19,10022,9001 in 14452
15Stanislaus County17,60021,2001 in 9358
16San Mateo County16,40019,7001 in 15623
17Sonoma County15,90019,1001 in 11543
18Tulare County14,50017,4001 in 9162
19Solano County14,20017,0001 in 1155
20Monterey County12,40014,9001 in 10434
21Placer County11,90014,3001 in 1323
22Santa Barbara County11,40013,8001 in 11566
23Merced County8,80010,5001 in 9184
24San Luis Obispo County8,50010,2001 in 12367
25Santa Cruz County7,6009,1001 in 12404
26Shasta County7,4008,9001 in 9705
27Marin County7,0008,4001 in 1526
28Butte County7,0008,4001 in 10192
29El Dorado County6,8008,1001 in 12101
30Madera County5,7006,9001 in 80
31Imperial County5,5006,6001 in 90
32Humboldt County5,2006,3001 in 9510
33Yolo County4,8005,7001 in 120
34Kings County4,7005,6001 in 889
35Napa County4,2005,0001 in 1267
36Mendocino County4,0004,8001 in 90
37Nevada County3,9004,7001 in 1154
38Sutter County3,5004,1001 in 9177
39Lake County3,3004,0001 in 811
40Yuba County2,9003,5001 in 80
41Tehama County2,8003,3001 in 80
42Calaveras County2,3002,7001 in 917
43Tuolumne County2,2002,7001 in 100
44Siskiyou County2,1002,5001 in 8191
45San Benito County1,9002,3001 in 110
46Amador County1,9002,2001 in 10156
47Lassen County1,2001,4001 in 80
48Del Norte County1,2001,4001 in 80
49Glenn County1,0001,2001 in 90
50Trinity County9601,2001 in 70
51Plumas County9201,1001 in 90
52Mariposa County7509001 in 100
53Colusa County7108501 in 961
54Inyo County6808201 in 100
55Modoc County4405201 in 80
56Mono County4305101 in 100
57Sierra County1902301 in 80
58Alpine Countyfewer than 50501 in 110

Methodology

How we estimate the gap

A modeled estimate from public data only. It is not a count of patients and contains no patient information.

missing = adults 50 to 80 × county smoking rate × national eligibility factor × (1 − state screening rate)

  • Adults 50 to 80: U.S. Census Bureau, Population Estimates, Vintage 2025
  • Smoking: CDC PLACES 2025 release (Kentucky and Pennsylvania: 2024 release)
  • Eligibility: USPSTF 2021 criteria, scaled to about 14.5 million eligible adults nationally
  • Screening rates: American Lung Association, State of Lung Cancer 2025
  • Who is missing: Census population estimates (age) and American Community Survey 2020 to 2024 (language)
  • Screening activity: CMS Medicare fee-for-service claims for low-dose CT (CPT 71271), 2024, by provider location

Estimates under 50 are shown as "fewer than 50"; others are rounded. Full methodology

Many of them are already your patients.

Oatmeal Health helps health systems and community health centers find, navigate, and screen the people who qualify, alongside the care teams you already have.

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