E-Epidemiology
Contingency table
Activity: Contingency table
Here is the 2x2 table describing the distribution of the animals in your study group, considering both their health status and their test result. This table is called contingency table or cross table. The letters a, b, c, and d refer to the number of animals in each category or cell.
Have a look at this 2 column and 2 row (i.e. 2x2) contingency table. The following test outcomes are possible:
- true-positive
- true-negative
- false-positive
- false-negative
Let's make sure you've understood this. Type the names of the possible test outcomes (e.g. "true-positive", "true-negative") into the contingency table below:
| Disease + |
Disease - | Total | |
| Test + |
a |
b |
a + b |
| Test - | c |
d |
c + d |
| Total | a + c | b + d | a + b + c + d |