Lecture 1 and 2 Flashcards
What makes a good diagnostic test?
80% Sensitivity and Specificity
> 3 Positive Likelihood Ratio
<0.33 Negative Likelihood Ratio
Contractile problem
(PROM, AROM, IMT, MMT, PAM)
PROM>AROM (when you go through AROM, muscles aren’t involved as much so can go further)
PROM: normal (or better than AROM)
AROM: reduced or painful (contractile injury so painful)
IMT: pain or discomfort
MMT: pain or discomfort
PAM: no pain (joint play, so won’t hurt a muscle)
Non-Contractile (structural/joint) problem (PROM, AROM, IMT, MMT, PAM)
PROM = AROM
PROM: normal or limited by pain and stiffness
AROM: normal or limited by pain and stiffness
IMT: no pain
MMT: no pain
PAM: pain or discomfort or stiffness (joint play so painful)
High specificity rules…
In
High sensitivity rules…
Out
What does high specificity mean?
positive results tends to rule in diagnosis
If you have positive test, it’s likely you have the condition (True Positive)
What does low specificity mean?
If you have positive test, you may not have the condition (False Positive)
What does high sensitivity mean?
Negative result rules out the diagnosis
If you have a negative test, it’s likely you don’t have the condition (True Negative)
What does low sensitivity mean?
If you have a negative test, you may still have the condition (False negative)
Formula for Positive LR
LR+ = Sensitivity / (100-Specificity)
Formula for Negative LR
LR- = (100-Sensitivity) / Specificity
How do you interpret a +LR post test probability
The probability that the diagnosis is true. (% that a positive test means you have the condition - true positive)
How do you interpret a -LR post test probability
% that you still have the condition, even though the test is negative (False negative)
