What is the specificity of anti-citrullinated protein antibodies (ACPA) when positive? A) 95% B) 75% C) 85% D) 100%
Understand the Problem
The question is asking for the specificity percentage of anti-citrullinated protein antibodies (ACPA) when they are positive, presenting multiple choice options for the answer.
Answer
95%
The final answer is 95%
Answer for screen readers
The final answer is 95%
More Information
The specificity of anti-citrullinated protein antibodies is typically high, generally between 88-98%, with figures often cited around 95%. This makes them highly specific for diagnosing rheumatoid arthritis.
Tips
Confusing sensitivity with specificity is common; ensure you are clear on their differences. Sensitivity measures the proportion of actual positives correctly identified, whereas specificity measures the proportion of actual negatives correctly identified.
Sources
- Anti-Citrullinated Protein Antibodies (ACPA) Assays and their Role in - pmc.ncbi.nlm.nih.gov
- Anti-Cyclic Citrullinated Peptide Antibody - Medscape Reference - emedicine.medscape.com