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The Lung Screening Study (LSS) was a pilot study designed to assess the feasibility of conducting a large scale randomized controlled trial (RCT) of low radiation dose spiral computed tomography (LDCT) versus chest X-ray (CXR) for lung cancer screening. During the fall of 2000, six PLCO screening centers recruited a total of 3,318 heavy or long-term smokers who were not participants in the PLCO trial and randomized them to receive either a screening LDCT scan (1,660 participants) or screening posteroanterior view chest radiograph (CXR) [1,658 participants].

The results of the LSS demonstrated convincingly the feasibility of an RCT of LDCT scanning in the United States.

Study Years: 2000-2002

Randomized trial with two arms:

  • Arms
    • Arm I: Screening LDCT scan
    • Arm II: Screening posteroanterior view chest radiograph (CXR)

Study Eligibility:
  • Ages Eligible for Study: 55-74
  • Sexes Eligible for Study: Male and Female
  • Not enrolled in PLCO trial
  • Current/Former Heavy smokers