a test or a set of tests intended to remove or detect defective items or those likely to exhibit early failures
Any testing procedure designed to separate people or objects according to a fixed characteristic or property. ... (05 Mar 2000) ... 
any test used to eliminate those who are definitely not affected by the disease in question, the remainder (those with positive reactions) being subjected to more refined diagnostic tests.
A test to observe the response of a range of plant cultivars or types to virus infection.
Type: Term Definitions: 1. any testing procedure designed to separate people or objects according to a fixed characteristic or property, with the intention of detecting early evidence of disease.