Flashcards in Variationin medicine/Diagnostic testing Deck (11)
What is nominal data?
What is ordinal data?
Ordered data, but not on a numerical scale (i.e. cancer stage). Cannot calculate an average of these types of data
When should you not use standard deviation?
When data are skewed or bimodal. Standard deviation only should be calculated if there is a normal distribution
What is sensitivity?
Percent of positive tests in people with the condition
What is specificity?
Percent of negative test results in people who do not have the disease
What is positive predictive value?
The probability that somebody actually has the disease if they test positive
What is negative predictive value?
The probability that somebody does NOT have the disease if they receive a negative test result
To rule in a disease, what kind of test do you want?
Test with high specificity
To rule out a disease, what kind of test do you want?
Test with high sensitivity
PPV is more affected by changes in sensitivity or specificity?