In screening, two tests are often necessary each with different performance characteristics. These may be offered at the same time (parallel testing) or sequentially (serial testing) [1].

Parallel versus serial testing.

Testing strategy:

Parallel testing

Serial testing

Procedure:

Two screening tests performed at the same time and the results are subsequently combined

Second screening test is performed only if the result of the first screening test is positive

Effect:

Higher sensitivity but lower specificity

Improves specificity at the cost of lower sensitivity

References


1. Sheringham J, Kalim K, Crayford T. Mastering Public Health: A guide to examinations and revalidation. ISBN-13 978-1-85315-781-3.