MS-1862

MS-1862

Antinuclear antibodies (ANA) are commonly found in elderly patients with systemic lupus erythematosus (SLE). However, they can also be found in around 9% of elderly people without the condition. Therefore, as a test for diagnosing SLE, ANA has low:

Positive predictive value
15%

Sensitivity
19%

Specificity
56%

Negative predictive value
9%

Incidence
1%

If a test is falsely positive in 9% of the elderly population then that test has poor specificity.

Low specificity tests have many false positives (those without the condition test positive).

Low sensitivity tests have many false negatives (those with the condition are missed).