Health communication and Stepped Reminders intervention for lung cancer screening: Larch Trial
Abstract
Importance
For >10 years, the US Preventive Services Task Force has recommended annual lung cancer screening (LCS), but adherence to annual screening remains low.
Objective
To test two multilevel, patient-centered interventions to increase adherence to guideline-concordant annual LCS. DESIGN,
Setting
AND
Participants
A pragmatic 2×2 factorial randomized clinical trial conducted at Kaiser Permanente Washington among patients who completed LCS with normal findings from November 21, 2022, to April 5, 2024. The date of last follow-up was July 4, 2025.
Interventions
The four arms included: usual care (n=459); health communication (n=460); ‘Stepped Reminders’ (n=460); or both interventions (n=458). The health communication intervention addressed patient screening knowledge barriers with print and video messaging. Stepped Reminders intervention pended LCS scan orders primary care physicians (PCP) and sent outreach to patients to remind them to schedule scans. Both interventions were facilitated by system-level LCS Coordinator with EHR registry to deliver interventions. MAIN OUTCOMES AND MEASURES The primary outcome was completion of screening low-dose computed tomography (LDCT) or chest CT 9 to 15 months after index LDCT. All participants eligible for annual screening were included in the modified intent-to-treat analysis. Participants were censored due to lung cancer diagnosis, death, early LDCT or chest CT, or disenrollment from health plan.
Results
Among 1837 trial participants, the mean age was 66.3 years (SD 6.5); 897 (48.8%) were female; 1572 (88.5%) were non-Hispanic White and 54 (3.0%) were Black; and 875 (47.6%) were currently using tobacco. Adherence to annual screening was 4.7% lower in those who received the health communication intervention (59.2% [476/804] vs 63.3% [516/815]; relative risk, 0.93, 95% CI 0.86, 1.00. p=0.04) relative to no communication, and 27.7% higher in those who received Stepped Reminders intervention (75.5% [604/800] vs 47.4% [388/819]; relative risk, 1.59, 95% CI 1.47, 1.72, p<0.001 relative to no reminder). Stepped Reminders improved screening rates significantly among participants currently using tobacco compared with former users (Risk difference 32.3% vs 24.1%, p=0.03).
Conclusions
AND RELEVANCE: Appropriately timed multilevel ‘reminders’ directed to PCPs to order and patients to schedule LDCT scans are effective to improve annual LCS adherence in programs led by PCPs. TRIAL REGISTRATION: ClinicalTrials.gov number NCT05747443, https://clinicaltrials.gov/study/NCT05747443?id=NCT05747443&rank=1