буду благодарна за малейшее прояснение ситуации.
контекст:

Triplicate replicates of the test article, positive control and untreated blood control tubes, were exposed to the appropriate volume of blood.
... compared to the untreated blood while the negative control had a coagulation time withing laboratory ranges.

Вот нашел фразу "The remaining samples collected into EDTA tubes were left untreated until processing"