Core biostatistics and epidemiology formulas including sensitivity, specificity, relative risk, and study design, as cloze cards with each term defined.
35 cards · cloze cards · AI-written, checked twice. Edit anything.
- Sensitivity is calculated as ____.
- true positives / (true positives + false negatives)
- Specificity is calculated as ____.
- true negatives / (true negatives + false positives)
- Positive predictive value (PPV) is calculated as ____.
- true positives / (true positives + false positives)
- Negative predictive value (NPV) is calculated as ____.
- true negatives / (true negatives + false negatives)
- A highly sensitive test, when its result is negative, is used to ____ disease (mnemonic SnNout).
- rule out
- A highly specific test, when its result is positive, is used to ____ disease (mnemonic SpPin).
- rule in
- Prevalence is defined as the ____.
- proportion of a population that has a disease at a given point in time
- Incidence is defined as the ____.
- rate at which new cases of a disease occur in a population over a specified time period
- How does positive predictive value change as disease prevalence increases, if a test's sensitivity and specificity stay constant?
- PPV increases
- How does negative predictive value change as disease prevalence increases, if a test's sensitivity and specificity stay constant?
- NPV decreases
- Relative risk is calculated as ____.
- incidence in the exposed group divided by incidence in the unexposed group
- Relative risk is the primary risk measure calculated in which type of study design?
- Cohort study
- In a 2x2 exposure/disease table with cells a, b, c, d, the odds ratio is calculated as ____.
- (a x d) / (b x c)
- An odds ratio closely approximates relative risk under what condition?
- When the disease being studied is rare.
- Odds ratio is the primary risk measure calculated in which type of study design?
- Case-control study