Sensitivity & Specificity; PPV & NPV
The probability of a true positive if the patient has the disease.
What is sensitivity?
dichotomous variable
What are categorical (or nominal) variables - only two choices
What is the amount of illness present in the population divided by the entire population?
What is prevelence?
A researcher wants to use scales that are continuous to measure variables. What would you use for the measurement?
What is interval and ratio?
Researchers asked patients if they how they rate their pain from 0 to 10 (with 10 being the worst. What is the level of measurement of the dependent variable?
What is ordinal?
In a study there is it was determined there is not association between the two variables. You know this means?
what is the p-value was greater than the alpha?
Reading a study that examines the relationship in women between being
over age 55 and colon cancer. The dependent variable is
What is colon cancer?
What is the average distance that the variables in a distribution are from the center.
What is standard deviation?
Formula to calculate the specificity of a screen.
What is true negatives (D)/all those who do not have the disease (A&B)?
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a study to examine effect of treatment without randomization
non-randomized control trial or quasi-experimental
The null hypothesis means what?
What is "that no relationship, association or difference exist between the two variables of interest?
An indicator of the center of the data
What is central tendency?
Prevalence
a reasonable estimate for pretest probability;
the number of existing cases of a condition within a population at a given time.
Clinical prediction rule - LR+ was 5.2 (LR-) was .25 with a pretest probability of 45%. What is true?
The test will be better at identifying those without sleep apnea.
If the LR+ is large, how is this interpreted?
A test for the presence of HIV has a positive predictive value (PV+) of 83%. How do you interpret this?
83% of those individuals who test positive for HIV are likely to have virus