OSCE Critical Appraisal

Question 1

Likelihood ratio

Answer 1

Ratio of the probability that the result is correct to probability that the result is incorrect
Negative LR for negative test result
Positive LR for positive test result
Can be applied to bayes theorem

Question 2

Define cohort study

Answer 2

Group of people with similar characteristics;
Acute and episodic vestibular syndromes

Question 3

Define prospective longitudinal study

Answer 3

Patients enrolled and observations recorded going forward over time

Question 4

Define sensitivity

Answer 4

Of the true positives (central cause) Proportion of people that tested positive

Question 5

Define specificity

Answer 5

Of true negatives (not central) proportion of those that tested negative

Question 6

Negative predictive value

Answer 6

Proportion of people who test negative that are negative for the condition (central vertigo)

Question 7

Positive predictive value

Answer 7

Proportion of patients that tested positive that have the condition (central vertigo)

Question 8

Predictive values dependent on

Answer 8

Prevalence of condition (central vertigo)
Low prevalence gives high negative predictive value

Question 9

Likelihood ratio in application

Answer 9

Bayes theorem
Using a pre test probability and a LR will give you a post test probability.