Skip to Main Content

An official website of the United States government

Government Funding Lapse

Because of a lapse in government funding, the information on this website may not be up to date, transactions submitted via the website may not be processed, and the agency may not be able to respond to inquiries until appropriations are enacted. The NIH Clinical Center (the research hospital of NIH) is open. For more details about its operating status, please visit  cc.nih.gov. Updates regarding government operating status and resumption of normal operations can be found at OPM.gov.

The Schema is a timeline of the study. It indicates start/end points, visits expected, major testing to be done, and any other information that is crucial to understanding how the study was completed.



Mayo Clinic outpatients were considered for this trial and went through an initial referral, interview, questionnaire, and signing an informed consent form before being randomized. The trial lasted for 6 years. After randomization, participants received a prevalence screen, PA & lateral chest x-ray, and a 3-day spontaneous sputum cytology. The control arm of the study was advised to receive annual chest x-rays and sputum cytology as well as receiving an annual questionnaire. The intervention arm was provided PA & lateral chest x-rays and 3-day spontaneous sputum cytology every 4 months until trial end.