Activity Status

  • 17-18 March 2010 Project kickoff
  • Development of Decision Support functionality as part of WP4.
  • Demonstration of activities on this web-site
  • 1 April 2011 WP4 model and software development meeting
  • 26-27 May 2011 Project Meeting
  • 22 September 2011 WP4 meeting
  • 1 November 2011 WP4 modeling meeting
  • 2 February WP4 meeting
  • 24 February 2012 Midterm meeting
  • 14 May 2012 WP 4 meeting
  • 20 June 2012 Annual meeting
  • 6 July 2012 WP4 modeling meeting
  • 15 March 2013 WP4 modelling meeting
  • 15 September 2013 Annual meeting

Chest Clinic

By: Lauritzen & Spiegelhalter, 1988

Asia is a small Bayesian network that calculates the probability of a patient having tuberculosis, lung cancer or bronchitis respectively based on different factors - for example whether or not the patient has been to Asia recently.

Shortness-of-breath (dyspnoea) may be due to tuberculosis, lung cancer, bronchitis, more than one of these diseases or none of them. A recent visit to Asia increases the risk of tuberculosis, while smoking is known to be a risk factor for both lung cancer and bronchitis. The results of a single chest X-ray do not discriminate between lung cancer and tuberculosis, as neither does the presence or absence of dyspnoea.

If we learn the fact that a patient is a smoker, we will adjust our beliefs (increased risks) regarding lung cancer and bronchitis. However, our beliefs regarding tuberculosis are unchanged (i.e., tuberculosis is conditionally independent of "smoking" given the empty set of variables). Now, suppose we get a positive X-ray result for the patient. This will affect our beliefs regarding tuberculosis and lung cancer, but not our beliefs regarding bronchitis (i.e., bronchitis is conditionally independent of X-ray given smoking). However, had we also known that the patient suffers from shortness-of-breath, the X-ray result would also have affected our beliefs regarding bronchitis (i.e., "bronchitis" is not conditionally independent of "X-ray" given "smoking" and "dysponea").

Patient has dyspnoea? Tuberculosis yes
Visit to Asia? Lung cancer yes
Patient is smoker? Bronchitis yes
X-ray photo is positive?    

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