You perform a clinical efficacy test and get the following results: Assay is negative - Unaffected by Disease or Condition: 40, Affected by Disease or Condition: 5. Assay is positive - Unaffected by Disease or Condition: 10, Affected by Disease or Condition: 45. What is the number of false-negative results?

To determine the number of false-negative results, we need to understand what a false-negative result represents in the context of a clinical assay. A false-negative occurs when the test fails to identify a condition that is present—in this case, it means the test is negative despite the individual actually being affected by the disease or condition.

In the provided results, we are particularly interested in how many individuals with the disease or condition received a negative test result. The data indicates that 5 individuals who are affected by the disease received a negative result. This specific count reflects the definition of a false negative because these individuals were indeed affected but the test incorrectly labeled their status as negative.

Therefore, the number of false-negative results is correctly identified as 5, which aligns with the understanding of what constitutes a false negative in a diagnostic assay.