Clinical Decision Support Systems

Practice Questions

 

 


1. Decision support tools for clinical consultation do not generally require

a. a systematic vocabulary and syntax for machine representation of medical information

b. a medical knowledge base and means of routinely updating it

c. the ability to process patient data of varying degrees of completeness

d. an "inference engine" based on logical deduction

e. the ability to express the "reasons" supporting their recommendations

ANSWERS


2.  In principle, expected value decision making assumes all but which of the following?

a. all outcomes relevant to making the decision may be represented numerically

b. any relevant outcomes that are qualitatively different (e.g. death vs. severe pain) may nevertheless be reexpressed and compared on the same numerical scale

c. physicians and patients are in generally close agreement on the utilities of different outcomes

d. a decision that produces the highest benefit, on the average over all patients, is better than a different decision that protects the most patients against the worst result

e. a decision that produces the highest benefit, on the average over all patients, is better than a different decision that produces the best result for the most patients

ANSWERS


3.  In the context of medical decision analysis, sensitivity analysis refers to

a. evaluating the sensitivity of a diagnostic laboratory test used in arriving at the decision

b. using the sensitivity of the laboratory test in Bayes' Theorem to calculate the positive predictive value of a diagnostic laboratory test result, for use in arriving at the decision

c. using the sensitivity of the laboratory test in Bayes' Theorem to calculate the negative predictive value of a diagnostic laboratory test result, for use in arriving at the decision

d. determining how large a change in the assumed sensitivities of any diagnostic tests used in arriving at the decision, changed individually or in combination, is necessary to produce a change in the recommended decision

e. determining how large a change in each of the assumed parameters of a decision analysis, changed individually or in combination, is necessary to produce a change in the recommended decision

ANSWERS


4.  Appendicitis is suspected in a 15 year old boy with right lower quadrant pain persisting for 2 days with increasing severity, anorexia, no nausea or vomiting, 2 loose stools/day, rectal temp 38C, normal urinanalysis, and WBC 15,000 with left shift.   Assume that with these signs and symptoms the probability of appendicitis is 30%, that operative mortality for appendectomy is 0.1%, and that when surgery is delayed until the appendix perforates the mortality is 1%. Now sSuppose that a non-invasive diagnostic test, with sensitivity of 70% and specificity of 90%, were available for appendicitis. The test is inexpensive, and quick enough that there is negligible risk associated with delaying long enough to get the result. Should a physician aiming to minimize mortality perform the test? Justify your answer.

ANSWERS