Prep for USMLEPrep for USMLE
         Forum      |     Resources New Posts   |   Register   |   Login





 3 part sequential question  



Post Reply  
  • 0/5
  • 1
  • 2
  • 3
  • 4
  • 5


Author1 post
  #1

An imaginary study involving 650 people was conducted to assess the performance of the stool antigen assay in detecting a helicobacter pylori infection. After collecting all the test results, it was found that 250 people tested positive and 400 people tested negative. If the positive and negative predictive value were 80% and 75%, respectively, then what proportion of people with the infection were identified by the test?

(A) 300/650
(B) 200/250
(C) 200/300
(D) 200/650


How would the sensitivity of the test change if the number of positive tests was higher?

(A) It would increase
(B) It depends on the prevalence
(C) Not enough information is provided
(D) It would decrease


What would the sensitivity of the test be if 10 people with the condition did not test negative?

(A) 200/310
(B) 210/300
(C) 210/310
(D) 200/300


The answers and explanations can be found on youtube via this link... https://www.youtube.com/watch?v=2fe_kjH_bbk







Bookmark and Share





Login or Register to post messages








show Similar forum topics

Sequential loss of hormones
Sequential Questions & Lab Values
Goljan part 1 or both part 1 and 2 for step 1
show Related resources

Conrad Fischer's Internal Medicine Question Book








Advertise | Support | Privacy | TOS | Premium | Contact