Sensitivity and specificity


Cat Eyes (#30793) by mark sebastian Attribution-NonCommercial-ShareAlike License

If you are reading about diagnostic tests you will often come across the terms sensitivity and specificity which are a measure of the performance of the test given a particular interpretation (cut-off). If you have trouble remember which is which try thinking about the everyday definitions of the words.

Sensitivity: “ability to perceive; readily and acutely affected by some particular influence”. In other words: how well a test detects the disease. A test that is very sensitive will pick up most of the real cases.

Specificity: “having a special determining quality; peculiar to, characteristic of, something”. In other words how particular the test result is. A test that is very specific will tend to only give positive results for real cases.

Some more on sensitivity and specificity:

D G Altman, J M Bland (1994) Statistics Notes: Diagnostic tests 1: sensitivity and specificity, BMJ 308:1552



Leave a comment

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s