It's eye-opening to realize how many tests with reasonable-appearing sensitivity or specificity will end up being worthless or weak.  The figure below classifies tests into four groups depending on the strongest level of evidence that they can provide:
Only tests falling along the very edge of this plot (green area) are capable of providing strong evidence.  Most tests will end up providing misleading or weak results, which often occurs despite having a specificity or sensitivity >80%.
#Diagnosis #Statistics #Test #Classification #Strength #Sensitivity #Specificity #Graph