Originally Posted by Sarrial Banda

AoA,

Respected members, I was studying psychology & came across these two terms i.e "Sensitivity & Specificity". I am stuck on these two & am unable to understand the relationship of Sensitvity with "True Positive prediction" & relationship of Specificity with "True Negative Prediction". The more I study, the more I get confused. Here is a googled explanation copied below for reference. Please help me in understanding these terms!!!!


Sensitivity and specificity are terms used to evaluate a clinical test. They are independent of the population of interest subjected to the test.

Positive and negative predictive values are useful when considering the value of a test to a clinician. They are dependent on the prevalence of the disease in the population of interest.

The sensitivity and specificity of a quantitative test are dependent on the cut-off value above or below which the test is positive. In general, the higher the sensitivity, the lower the specificity, and vice versa.

Source: http://ceaccp.oxfordjournals.org/content/8/6/221.full