What is the formula for calculating true negative rate?

The true negative rate, also known as specificity, is calculated using the number of true negatives in relation to the total number of actual negatives. The formula for this is true negatives divided by the sum of true negatives and false positives. This means that true negatives represent the count of correctly identified negative cases, while the denominator accounts for all actual negative instances, encompassing both the true negatives and the false positives.

Understanding this concept is crucial in diagnostic testing, as a higher true negative rate indicates that the test is effective at correctly identifying individuals who do not have the condition of interest. The other options do not accurately reflect the calculation of the true negative rate as they either focus on other components of diagnostic testing or measure different rates entirely. Thus, the correct answer captures the essence of specificity in diagnostic evaluation.