For questions 6 to 9: How accurate is the VDRL test for syphilis? Data below are from 189 syphilis cases and 213 unaffected individuals and a VDRL test for syphilis. You want to know how accurate the VDRL test is for syphilis. Syphilis Normal VDRL test result + 170 7 19 206 6) What is the sensitivity? (1 pt) 7) What is the specificity? (1 pt) 8) What is the positive predictive value of the test? (2 pts) 9) What is the negative predictive value of the test? (2 pts) 10) Is it feasible to examine the validity of self-reported syphilis on an online class survey? Why/why not. (2 pts)