Which term describes a laboratory finding that is not final and requires confirmatory analysis?

• A. Probable negative
• B. Probable positive
• C. Presumptive positive
• D. Confirmed positive

Answer: (C)

When a lab result isn’t final and still needs a confirmatory step, it’s described as presumptive positive. The initial test has given a positive signal, but that signal isn’t considered conclusive until a more specific, definitive confirmatory test verifies it. This distinction matters because screening assays are designed to be rapid and sensitive, but they can yield false positives or less certainty, so a follow-up confirmatory analysis is required to rule in or out the result.

In FSIS practice, a presumptive positive prompts appropriate actions and further testing, while a confirmed positive is the definitive result after confirmation. The other terms don’t fit standard lab reporting: “probable” isn’t used for final or provisional results in this context, and “confirmed positive” describes the final, verified finding rather than the provisional one.