Abstract
BACKGROUND: In 2013, the US Preventive Services Task Force (USPSTF) issued recommendations for low-dose computed tomography for lung cancer screening (LDCT-LCS), but there continues to be a dearth of information on the adoption of LDCT-LCS in healthcare systems. Using a multilevel perspective, our study aims to assess referrals for LDCT-LCS and identify facilitators and barriers to adoption following recent policy changes. METHODS: A retrospective analysis of electronic medical record data from patients aged 55-80 years with no history of lung cancer who visited a primary care provider in a large healthcare system in California during 2010-2016 (1,572,538 patient years). Trends in documentation of smoking history, number of eligible patients, and lung cancer screening orders were assessed. Using Hierarchical Generalized Linear Models, we also evaluated provider-level and patient-level factors associated with lung cancer screening orders among 970 primary care providers and 12,801 eligible patients according to USPSTF guidelines between January 1st, 2014 and December 31st, 2016. RESULTS: Documentation of smoking history to determine eligibility (59.2% in 2010 to 77.8% in 2016) and LDCT-LCS orders (0% in 2010 to 7.3% in 2016) have increased since USPSTF guidelines. Patient factors associated with increased likelihood of lung cancer screening orders include: younger patient age (78-80 vs. 55-64 years old: OR, 0.4; 95% CI, 0.3-0.7), Asian race (vs. Non-Hispanic White: OR, 1.6; 95% CI, 1.1-2.4), reported current smoking (vs. former smoker: OR, 1.7; 95% CI, 1.4-2.0), no severe comorbidity (severe vs. no major comorbidity: OR = 0.2, 95% CI = 0.1-0.3; moderate vs. no major comorbidity: OR = 0.5; 95% CI = 0.4-0.7), and making a visit to own primary care provider (vs. other primary care providers: OR, 2.4; 95% CI, 1.7-3.4). Appropriate referral for lung cancer screening varies considerably across primary care providers. Provider factors include being a female physician (vs. male: OR, 1.6; 95% CI, 1.1-2.3) and receiving medical training in the US (foreign vs. US medical school graduates: OR = 0.4, 95% CI = 0.3-0.7). CONCLUSIONS: Future interventions to improve lung cancer screening may be more effective if they focus on accurate documentation of smoking history and target former smokers who do not regularly see their own primary care providers.