CAP recommends including how many tissue samples in the antibody validation set?

CAP recommends including how many tissue samples in the antibody validation set?

• A. Minimum of 10
• B. Minimum of 15
• C. Minimum of 50
• D. Minimum of 25

Answer: (D)

Adequate sample size for antibody validation in immunohistochemistry relies on having enough tissue diversity to assess how the antibody performs across different contexts. CAP guidance requires a minimum of 25 tissue samples in the validation set so you can include tissues with known positive staining, known negatives, and a range of expression levels. This breadth helps reveal potential cross-reactivity and ensures scoring is reliable across samples. Using fewer samples risks missing tissue-specific effects or rare false positives, making validation less robust. While more samples can strengthen confidence, 25 is the standard minimum CAP specifies.

Adequate sample size for antibody validation in immunohistochemistry relies on having enough tissue diversity to assess how the antibody performs across different contexts. CAP guidance requires a minimum of 25 tissue samples in the validation set so you can include tissues with known positive staining, known negatives, and a range of expression levels. This breadth helps reveal potential cross-reactivity and ensures scoring is reliable across samples. Using fewer samples risks missing tissue-specific effects or rare false positives, making validation less robust. While more samples can strengthen confidence, 25 is the standard minimum CAP specifies.