Project Summary

PCORI has identified the need for large studies that look at real-life questions faced by diverse patients, caregivers, and clinicians. To address this need, PCORI launched the Pragmatic Clinical Studies initiative in 2014. Pragmatic clinical studies allow for larger-scale studies with longer timelines to compare the benefits and harms of two or more approaches known to be effective for preventing, diagnosing, treating, or managing a disease or symptom. They focus on everyday care for a wide range of patients. This research project is one of the studies PCORI awarded as part of this program.

This research project is in progress. PCORI will post the research findings on this page within 90 days after the results are final.

What is the research about?

Every year, about 1.5 million Americans learn they have a nodule, or a spot or small growth, on their lungs. Most small nodules are harmless, but some are caused by cancer. Lung cancer is the leading cause of cancer deaths in the United States. The most common type of lung cancer is sometimes curable if found early.

Professional medical groups recommend regular lung cancer screening for people who smoke or have a history of heavy smoking. The goal of screening is to find lung cancer at an early stage, when successful treatment is possible. A scan of the chest, called computed tomography or a CT scan, is the most accurate test for lung cancer. If a CT scan finds a nodule, doctors may recommend regular follow-up CT scans to check whether the nodule grows or changes over time. However, doctors don’t always know how often to scan patients who have a nodule.

One drawback of CT scans is that doctors may find growths that aren’t cancer. As a result, some patients get follow-up scans, tests, surgeries, or treatment that they don’t need. Patients and their families may also worry needlessly. In this study, the research team is comparing less and more frequent follow-up CT scans to find lung cancer early.

Who can this research help?

This research can help people with small nodules in their lungs and their doctors decide how often to repeat CT scans to see if a nodule is growing, which makes cancer much more likely.

What is the research team doing?

The research team is enrolling more than 47,000 patients at 26 hospitals over 20 months. The study focuses on adults ages 35 and older with small nodules in their lungs. Doctors found the nodules either by screening or by accident while doing a chest CT scan for some other reason. The team is assigning patients by chance to have either more frequent or less frequent follow-up CT scans. Doctors decide on the number of CT scans based on each patient’s risk factors and the nodule’s traits. The research team estimates that patients who have less frequent screening will get two CT scans for about every three scans given to patients who receive more frequent follow-up. 

The research team is following patients for two years to see if the cancerous nodules grow to a more advanced and less treatable stage of disease. The team is tracking how long patients live after a cancer diagnosis. The researchers also look at how many cancer-related tests and surgeries patients have, the radiation dose used for CT scans, how closely doctors followed screening recommendations, and how often patients got CT scans prescribed for them. Using internet surveys, the team is measuring patients’ emotional health and general health status two months after screening and then again each year.

A group of researchers, patients, doctors and other healthcare professionals, advocacy groups, and professional societies helps design and carry out the study.

Research methods at a glance

Design Elements Description
Design Randomized controlled trial
Population Adults ages 35 and older who have at least one small nodule (15 mm or less) in the lung, are not pregnant, and did not have a cancer diagnosis within the past five years (except nonmelanoma skin cancer)
  • More frequent chest CT scans to check for growth in a nodule found by screening or unexpectedly
  • Less frequent chest CT scans to check for growth in a nodule found by screening or unexpectedly

Primary: number of cancerous nodules that grow larger than 2 cm during follow-up

Secondary: time from nodule identification to cancer diagnosis; survival time from cancer diagnosis until death or completion of the study; patient-reported emotional distress, anxiety, and general health status; number of imaging tests, biopsy tests, and surgeries; radiation doses; number of recommended CT scans that were either not ordered by doctors or not completed by patients

Timeframe 2-year follow-up for primary outcome

Project Information

Michael K. Gould, MD, MS
Kaiser Foundation Research Institute, a Division of Kaiser Foundation Hospitals
Pragmatic Trial of More versus Less Intensive Strategies for Active Surveillance of Patients with Small Pulmonary Nodules

Key Dates

February 2015
August 2024

Study Registration Information


Award Type
Health Conditions Health Conditions These are the broad terms we use to categorize our funded research studies; specific diseases or conditions are included within the appropriate larger category. Note: not all of our funded projects focus on a single disease or condition; some touch on multiple diseases or conditions, research methods, or broader health system interventions. Such projects won’t be listed by a primary disease/condition and so won’t appear if you use this filter tool to find them. View Glossary
Populations Populations PCORI is interested in research that seeks to better understand how different clinical and health system options work for different people. These populations are frequently studied in our portfolio or identified as being of interest by our stakeholders. View Glossary
Intervention Strategy Intervention Strategies PCORI funds comparative clinical effectiveness research (CER) studies that compare two or more options or approaches to health care, or that compare different ways of delivering or receiving care. View Glossary
State State The state where the project originates, or where the primary institution or organization is located. View Glossary
Last updated: March 14, 2024