What Are the Main Types of Test Limitations?

Diagnostic tests are subject to several limitations that can affect their accuracy and usefulness. The main types include:

Sensitivity and Specificity: These are measures of a test’s ability to correctly identify those with and without the disease, respectively. A test with high sensitivity will have fewer false negatives, while a test with high specificity will have fewer false positives.
Predictive Values: Positive Predictive Value (PPV) and Negative Predictive Value (NPV) are affected by the prevalence of the disease in the population. A high prevalence increases PPV and decreases NPV, and vice versa.
Cross-reactivity: Some tests may react with non-target substances, leading to inaccurate results, such as false positives or negatives.
Sample Quality: The reliability of test results can be compromised by poor sample collection, handling, or storage.
Technical Limitations: These include issues related to the equipment, reagents, and methodologies used in testing.