Explain parallel interpretation of lab tests

• A. Parallel interpretation requires both tests positive
• B. With parallel interpretation, animals that test positive to one test, the other test, or both are positive
• C. Parallel interpretation uses sequential testing
• D. Parallel interpretation yields the same as series

Answer: (B)

In parallel interpretation, you label an animal as positive if either test comes back positive. This approach boosts sensitivity because you’re less likely to miss cases—an infected animal is more likely to test positive on at least one test, so broadening the positive criteria catches more true positives. However, it lowers specificity since a non-infected animal could be labeled positive if either test yields a false positive. So, the idea is: any positive on either test counts as overall positive. The statement that an animal is positive if it tests positive on one test, the other test, or both captures this exactly. The other descriptions describe requiring both tests to be positive (which is the opposite approach, often called serial or series testing) or sequential testing, and would not reflect parallel interpretation.