February, 2003
© 2000, 2001, 2003 Scott S. Emerson, M.D., Ph.D.
Screening Studies: 3
Medical Studies as Diagnostic Tests
Statistical hypothesis  testing as a diagnostic test
P value: Probability of observing positive (statistically significant) test in absence of true treatment effect
·Level of significance is 1 - specificity
·Common choice of a=.05 means specificity is 95%